ArticlePDF Available

A new tool to inform intra-operative decision making in skin cancer treatment: The non-invasive assessment of basal cell carcinoma of the skin using elastic scattering spectroscopy

Authors:

Abstract

The aim of this study was to evaluate the findings of elastic scattering spectroscopy co-registered with histopathology in patients with basal cell carcinoma against normal and some common benign skin disorders. Clinically suspicious head and neck skin lesions were included in this study. Those lesions with surrounding innocuous skin were interrogated by elastic scattering spectroscopy, co-registered biopsies were taken and examined histopathologically; the results were then compared using a variety of statistical techniques. Our analysis showed obvious and consistent spectral differences between normal and pathological skin. Discriminating elastic spectral differences were consistently identified between basal cell carcinoma and other skin lesions of similar appearance. This preliminary study shows that elastic scattering spectroscopy can distinguish between basal cell cancer, common benign conditions and variants of normal skin. Elastic scattering spectroscopy can also help determine the diagnosis between benign lesions with a high degree of accuracy suggesting that elastic scattering spectroscopy can add significant objectivity to dermatological diagnosis and management of even benign conditions.
Page 1 of 8
Compeng interests: none declared. Conict of interests: none declared.
All authors contributed to the concepon, design, and preparaon of the manuscript, as well as read and approved the nal manuscript.
All authors abide by the Associaon for Medical Ethics (AME) ethical rules of disclosure.
Original research study
   Upile T, Jerjes W, Johal O, Lew-Gor S, Mahil J, Sudhoff H. A new tool to inform intra-operative
   


Abstract
Introduction

-
  -
     
carcinoma against normal and some

Materials and methods
    
     
    -


    
-
-

Results
    
   -
 
Discriminating elastic spectral differ-
-

skin lesions of similar appearance.
Conclusion
    
elastic scattering spectroscopy can

-
ants of normal skin. Elastic scattering
    -
    
      -

   
A new tool to inform intra-operative decision making in skin cancer
treatment: the non-invasive assessment of basal cell carcinoma of
the skin using elastic scattering spectroscopy
T Upile32211
-
     
conditions.
Introduction
-
 -
     
 -

     -
    
-
        
     

    
    
-
     
    
-
-
   

    
   
    -
eas of cosmetic importance or near

 
important goals of disease removal

   -
    
    
      
proper treatment delivery and its ef-
-
    
     
    

 -

   
treatment.
    
-

and an improved prognosis for a pa-
     
    
    
-
  

   -
ment in ‘real-time’.
    

     
     
  

   
     -
  
    

       
related to its primary aetiology—

   -

neck    

       
     -
   -

     -
     
     
       
   
 -

is a good predictor of relative risk



1


2
 

3


   Upile T, Jerjes W, Johal O, Lew-Gor S, Mahil J, Sudhoff H. A new tool to inform intra-operative
   

Page 2 of 8
Compeng interests: none declared. Conict of interests: none declared.
All authors contributed to the concepon, design, and preparaon of the manuscript, as well as read and approved the nal manuscript.
All authors abide by the Associaon for Medical Ethics (AME) ethical rules of disclosure.
Original research study

-

     
   

   
      
    
    
   -
vanced disease.
     
-
     
     
    
    
    
    
    
      

   
in terms of errors of interpretation


    
weeks to complete and interpret).

    -
 
dependent.
     
 
    
    -


-
       -
     
-
 -
   



-

-
     
     
   


    -
   
   -
 -
    



    
     
  
consider elastic scattering spectros-
    
    
    -

-
 
-
-
 

     


  
 -
   

-
     
      
      -
   
      


    
   -
ganelles   
   -
   
-

 
    
-
    -
     
    
   
    

     
 -

     
non-invasively and in real-time.
Materials and methods
     
 -
     
    
     -

     
-
      -
      


   
      -
tailed2     

     
     
of concern. If excision was clinically
-

-
  
   


      
   
      
  
   
    

  
   
   
   
     
      -

-
    
     
     
    

    
Page 3 of 8
Compeng interests: none declared. Conict of interests: none declared.
All authors contributed to the concepon, design, and preparaon of the manuscript, as well as read and approved the nal manuscript.
All authors abide by the Associaon for Medical Ethics (AME) ethical rules of disclosure.
   Upile T, Jerjes W, Johal O, Lew-Gor S, Mahil J, Sudhoff H. A new tool to inform intra-operative
   

Original research study

   
  

 
 -
    

-
    
     

24.
Results
    
    
±


 -

    
 
    -


    
lesions for comparative analysis. No
    -

-


    
   
    -
    
-

     
-
     
     

in a cosmetically sensitive manner.

   

Statistical approach for model
generation and model validation
    
     


  2   
     -
 
-
    -
    

     

   -
    
    
   

discriminate analysis (LDA) strate-
     
-
       
   
-
   

   

    
    
-
-

Table 1 The 4 most common
pathologies of the paent populaon
studied
Diagnosis %
BCC 28.8
Intra-dermal naevus 21.9
Fibro-epithelial polyp 13.7
Seborrhoeic keratosis 9.6
Other benign lesions 26
Table 2 The number of pathological
sites interrogated and number of
site specic spectra obtained
Number
of sites
Number
of spectra
BCC 59 570
Intra-dermal
naevus
31 633
Fibro-epithelial
polyp
23 502
Benign
seborrhoeic
keratosis
12 269
Normal skin 125 551
400
2
500 600
Wavelength
700 800
1
0
Intensity
1
2
Figure 1: A representative elastic
     
   
   
-


5
0.0
0 5
Score
10
0.1
0.2
0.3
Frequency
0.4
0.5
400
2
1
0
Intensity
1
2
400 600
Wavelength
700 800
Figure 2:    
   -
   

    
-
     

 
plot2     
   
   
    -
sis (orange) spectra.
   Upile T, Jerjes W, Johal O, Lew-Gor S, Mahil J, Sudhoff H. A new tool to inform intra-operative
   

Page 4 of 8
Compeng interests: none declared. Conict of interests: none declared.
All authors contributed to the concepon, design, and preparaon of the manuscript, as well as read and approved the nal manuscript.
All authors abide by the Associaon for Medical Ethics (AME) ethical rules of disclosure.
Original research study


   
     
 
     -
    

 
-
     
   
   -
     
     

    -

    
-
     
 
      
   
   

    
   -

     
    
      
  
 
Table 3 Analysis results and ability of the elasc spectroscopy technique to discriminate between normal, benign and
malignant lesions. Also shown is the similar discriminang ability of the technique when comparing readings taken from
the periphery of a BCC and the centre of the BCC
Sensivity Specicity Accuracy
Per spectra Per site Per spectra Per site Per spectra Per site
BCC vs intra-dermal naevus 0.8789474 0.9859155 0.9787928 0.8846154 0.9306847 0.9587629
BCC vs bro-epithelial polyp 0.8385965 0.9577465 0.8884462 0.7826087 0.8619403 0.9148936
BCC vs benign seborrhoeic keratosis 0.9543860 1 0.9665428 0.9166667 0.9582837 0.9879518
BCC vs normal 0.8842105 0.9436620 0.7422868 0.4324324 0.8144514 0.6827586
BCC periphery vs BCC centre 0.115880 0.3750000 0.6720257 0.3939394 0.4319853 0.3846154
Intra-dermal naevus vs bro-epithelial polyp 0.8036466 1.0000000 0.8286853 0.6521739 0.8139918 0.8490566
Intra-dermal naevus vs benign seborrhoeic
keratosis
0.6579926 0.7500000 0.9929874 0.8666667 0.9012220 0.8333333
Fibro-epithelial polyp vs benign seborrhoeic
keratosis
0.8996283 0.9166667 0.9581673 0.7391304 0.9377432 0.8000000
0.0 0.2 0.4
0.0
0.6 0.8
1-specificity
1.0
0.2
0.4
0.6
Sensivity
0.8
1.0
Figure 3:     
   
   -
    
    

400
2
500 600
Wavelength
700 800
1
0
Intensity
1
2
Figure 4: A representative elastic
     

     
   

5
0.0
0 5
Score
10
0.2
0.4
0.8
Frequency
0.6
1.0
1.2
400
2
1
0
Intensity
1
2
400 600
Wavelength
700 800
Figure 5:    
   -
   
     
    -
    
  -
     
   2 

   



Compeng interests: none declared. Conict of interests: none declared.
All authors contributed to the concepon, design, and preparaon of the manuscript, as well as read and approved the nal manuscript.
All authors abide by the Associaon for Medical Ethics (AME) ethical rules of disclosure.
   Upile T, Jerjes W, Johal O, Lew-Gor S, Mahil J, Sudhoff H. A new tool to inform intra-operative
   

Original research study

-

    


-
      


     
 
     
    
   
operative cancer resection and
 -
    
     
    
since clones of differing aggressivity

   
 
-

Discussion
    
  -
    -
    
 
     -

    -
    -
      

    
 
-
    
     -
   
   
 -
terpreted as an indicative of cancer.
 
     -
      
      -
     
0.0 0.2 0.4
0.0
0.6 0.8
1-specificity
1.0
0.2
0.4
0.6
Sensivity
0.8
1.0
Figure 6:     
     
    
    

400
2
500 600
Wavelength
700 800
1
0
Intensity
1
2
Figure 7: A representative elastic
     
     
     
 
    
-


5
0.0
0 5
Score
10
0.1
0.3
0.2
0.4
0.5
400
2
1
0
Intensity
1
2
400 600
Wavelength
700 800
Figure 8:    
   -
     
     
    
     


2

    
    
  
 

   
-


Figure 9:
   


trade-off of sensitivity against specif-
-

    




     
     

-
   
   -
      

   

0.0 0.2 0.4
0.0
0.6 0.8
1-specificity
1.0
0.2
0.4
0.6
Sensivity
0.8
1.0
   Upile T, Jerjes W, Johal O, Lew-Gor S, Mahil J, Sudhoff H. A new tool to inform intra-operative
   


Compeng interests: none declared. Conict of interests: none declared.
All authors contributed to the concepon, design, and preparaon of the manuscript, as well as read and approved the nal manuscript.
All authors abide by the Associaon for Medical Ethics (AME) ethical rules of disclosure.
Original research study


-
     
   
       
lesions in a primary care setting2. It is


     -
     
    
-
      

 -


-


  
resection in primary care settings
    
-

    -
     -


-

patient care.
Challenges
     
  

    


     
-
  
-
-

2
-
     


-

400 500 600
2
700
Wavelength
800
1
0
1
Intensity
2
Figure 10:   -
 
    -
   
   
   
    
 -
-
nign lesions and normal.
Table 4 BCC vs normal skin results
Comparison of the histological diagnosis and ESS in the diagnosis of the skin pathology group
Test: ESS
diagnosis
Disease: BCC histological diagnosis (Gold standard)
Sites BCC Normal Total (n)
BCC (59) True posive (TP) 397 False posive (FP) 29 All with posive test = (TP + FP) 426
Normal (125) False negave (FN) 113 True negave (TN) 118 All with negave test = (FN + TN) 231
Total (n) All with disease 510 All without disease 147 All = (TP + FP + FN + TN) 657
Sensivity = TP/(TP + FN) 77.8%
Specicity = TN/(TN + FP) 80.3%
Pre-test probability = (TP + FN)/(TP + FP + FN + TN) 64.8%
Posive predicve value = TP/(TP + FP) 93.2%
Negave predicve value = TN/(FN + TN) 51.1%
0.0 0.2 0.4
0.0
0.6 0.8
1-specificity
1.0
0.2
0.4
0.6
Sensivity
0.8
1.0
Figure 11:  
    
    
   -
  

 -

     
    
    
    
    -
 
  
    


Compeng interests: none declared. Conict of interests: none declared.
All authors contributed to the concepon, design, and preparaon of the manuscript, as well as read and approved the nal manuscript.
All authors abide by the Associaon for Medical Ethics (AME) ethical rules of disclosure.
   Upile T, Jerjes W, Johal O, Lew-Gor S, Mahil J, Sudhoff H. A new tool to inform intra-operative
   

Original research study

      
-
cal intranodal metastasis in oral cancer
   

      
     
     
    


      

   -
  
    

      
-
cal intranodal metastasis in oral cancer
   

   -

    

      
     
  
   
     -
     

      

-
     
    


    
    -
gramme for oral cancer and precancer
     

      
      
    
      
    

 


      
     
    -
   
   
    
       
    
     -
      
   
      -
     
-
     
conditions.
Abbreviations list

   
    
   
   
  
-

Acknowledgement
     

Declaration

-
      
 
     

References

     
      
   

   
     -

   

        
       
   


      
-
     
-
    

  -
tion alone2 -
      
    



    -
  
 -
    
     

    


    

Conclusion
    
    
-

-
      
  
    
 -
   
     

     
    -
ness and non-operator dependence.
    
     -
  -
    
improve management and prognosis.
 -
-
     
-
-

     
-
    
     

     
-
     
   Upile T, Jerjes W, Johal O, Lew-Gor S, Mahil J, Sudhoff H. A new tool to inform intra-operative
   

Page 8 of 8
Compeng interests: none declared. Conict of interests: none declared.
All authors contributed to the concepon, design, and preparaon of the manuscript, as well as read and approved the nal manuscript.
All authors abide by the Associaon for Medical Ethics (AME) ethical rules of disclosure.
Original research study

     -
    -


-
    -
gramme for oral cancer and precancer
     

      
       
Elastic scattering spectroscopy for
     
   

   
    
044022.
    
diagnosis of non-melanoma skin cancer
     
   -


      
   
      

     

       
   

       
   

    
    

        
Real-time Raman spectroscopy for non-
invasive skin cancer detection—prelimi-



     
     
-
  
     

    
     
      
... ESS is a point measurement that is sensitive to the size and packing of dense subcellular components such as the nucleus, nucleolus, and mitochondria, as well as absorption by hemoglobin [9][10][11][12][13]. The size and density of these organelles change during transformation to premalignant or malignant conditions [10,[13][14][15]. ESS enjoys the advantage of being fast, reliable, and cost-effective and potentially offers a non-invasive, real-time, in situ diagnosis [13,14,16]. ...
... The size and density of these organelles change during transformation to premalignant or malignant conditions [10,[13][14][15]. ESS enjoys the advantage of being fast, reliable, and cost-effective and potentially offers a non-invasive, real-time, in situ diagnosis [13,14,16]. ...
Article
Full-text available
A B S T R A C T Introduction: There is a strong need for developing clinical technologies and instruments for prompt tissue assessment in a variety of oncological applications as smart methods. Elastic scattering spectroscopy (ESS) is a real-time, noninvasive, point-measurement, optical diagnostic technique for malignancy detection through changes at cellular and subcellular levels, especially important in early diagnosis of invasive skin cancer, melanoma. In fact, this preliminary study was conducted to provide a classification method for analyzing the ESS spectra. Elastic scattering spectra related to the normal skin and melanoma lesions, which were already confirmed pathologically, were provided as input from an ESS database. Materials and Methods: A program was developed in MATLAB based on singular value decomposition and K-means algorithm for classification. Results: Accuracy and sensitivity of the proposed classifying method for normal and melanoma spectra were 87.5% and 80%, respectively. Conclusion: This method can be helpful for classification of melanoma and normal spectra. However, a large body of data and modifications are required to achieve better sensitivity for clinical applications.
... 8 Also OCT images of oncological pathologies were tested using color, fractal, and texture features, 9 but the possibility of tumor diagnosis with these features is still under consideration 10 as malignant and premalignant tumors do not have distinctive patterns in OCT images. 11 Tumor diagnosis is possible with spectroscopy techniques, such as elastic scattering, 12 Raman spectroscopy (RS), 13 autofluorescence (AF) 14 analysis, and Stokes shift spectroscopy. 15 RS wavelength shift and intensity of inelastic scattering caused by interaction of light with different vibration types of tissue components were used for tumor classification in numerous investigations due to today's breakthroughs in detecting weak signals. ...
Article
Full-text available
In this work the study of the optical properties of skin tissues using Raman spectroscopy and autofluorescence analysis was performed. The analysis of different skin neoplasms was carried out based on the Raman and autofluorescence spectra stimulated by 785 nm laser. In this study the spectral data was processed by different mathematical methods allowed for effective classification of malignant and benign tumors. The proposed diagnostic methods helped to achieve 82.1-87% differentiation accuracy of skin neoplasms.
... 8 Also OCT images of oncological pathologies were tested using color, fractal, and texture features, 9 but the possibility of tumor diagnosis with these features is still under consideration 10 as malignant and premalignant tumors do not have distinctive patterns in OCT images. 11 Tumor diagnosis is possible with spectroscopy techniques, such as elastic scattering, 12 Raman spectroscopy (RS), 13 autofluorescence (AF) 14 analysis, and Stokes shift spectroscopy. 15 RS wavelength shift and intensity of inelastic scattering caused by interaction of light with different vibration types of tissue components were used for tumor classification in numerous investigations due to today's breakthroughs in detecting weak signals. ...
Article
The differentiation of skin melanomas and basal cell carcinomas (BCCs) was demonstrated based on combined analysis of Raman and autofluorescence spectra stimulated by visible and NIR lasers. It was ex vivo tested on 39 melanomas and 40 BCCs. Six spectroscopic criteria utilizing information about alteration of melanin, porphyrins, flavins, lipids, and collagen content in tumor with a comparison to healthy skin were proposed. The measured correlation between the proposed criteria makes it possible to define weakly correlated criteria groups for discriminant analysis and principal components analysis application. It was shown that the accuracy of cancerous tissues classification reaches 97.3% for a combined 6-criteria multimodal algorithm, while the accuracy determined separately for each modality does not exceed 79%. The combined 6-D method is a rapid and reliable tool for malignant skin detection and classification. © 2017 Society of Photo-Optical Instrumentation Engineers (SPIE).
Article
Novel optical-based diagnostic systems are promising technologies that can be used in the clinic providing the clinician with an adjunct to histopathological assessment and facilitating rapid diagnosis for patients. Aided by the use of differing wavelengths of light, these systems are capable of detecting changes within tissues and provide immediate results. We review the most common optical biopsy systems to detect oral and head and neck lesions and discuss their clinical applications. This article is protected by copyright. All rights reserved.
Article
Optical biopsy systems are a potential adjunct to the histopathological assessment of tissue specimens; they are not invasive and can give an immediate result. We review the most common optical biopsy techniques used to detect lesions of the head and neck: elastic scattering spectroscopy, microendoscopy, narrow band imaging, fluorescence, and optical coherence tomography, and discuss their clinical use.
Article
Full-text available
Background: Early detection of premalignant/malignant lesions in the oral cavity can certainly improve the patient's prognosis. This study presents fluorescence imaging with the topical application of 5-aminolevulinic as a way to improve detection of various oral tissue pathologies. This procedure depends mainly on comparing the intensity of red and green fluorescence emitted from tissues during examination. Materials and methods: Seventy-one patients who presented with clinically suspicious oral leukoplakia were recruited for this study. Each of the patients was required to have 5-aminolevulinic acid in the form of mouth rinse prior to fluorescence imaging. Following this a surgical biopsy was acquired from the exact examination site. The results of the fluorescence spectroscopy have been compared with histopathology. Results: A Student's t-test was applied to test the viability of the ratio between red and green fluorescence. The red-to-green ratio was found to increase significantly when the lesion was identified as dysplastic or carcinoma in situ. By applying a threshold line to discriminate between normal and dysplastic lesions; a sensitivity of 83-90% and specificity of 79-89% were obtained. Conclusion: Fluorescence spectroscopy combined with 5-aminolevulinic acid-induced protoporphyrin IX was found as a valuable tool in the diagnosis of oral premalignancy. This technique offers the potential to be advantageous over other non-optical techniques in terms of providing real-time diagnosis, in situ monitoring, cost effectiveness and more tolerated by patient compared to surgical biopsy.
Article
Full-text available
Endoscopic surveillance of Barrett's oesophagus currently relies on multiple random biopsies. This approach is time consuming, has a poor diagnostic yield, and significant interobserver variability. Elastic scattering spectroscopy is a real time in vivo optical technique which detects changes in the physical properties of cells. The aim of this study was to assess the potential for elastic scattering to detect high grade dysplasia or cancer within Barrett's oesophagus. Elastic scattering spectroscopy measurements collected in vivo were matched with histological specimens taken from identical sites within Barrett's oesophagus. All biopsies were reviewed by three gastrointestinal pathologists and defined as either "low risk" (non-dysplastic or low grade dysplasia) or "high risk" (high grade dysplasia or cancer). Two different statistical approaches (leave one out and block validation) were used to validate the model. A total of 181 matched biopsy sites from 81 patients, where histopathological consensus was reached, were analysed. There was good pathologist agreement in differentiating high grade dysplasia and cancer from other pathology (kappa = 0.72). Elastic scattering spectroscopy detected high risk sites with 92% sensitivity and 60% specificity and differentiated high risk sites from inflammation with a sensitivity and specificity of 79%. If used to target biopsies during endoscopy, the number of low risk biopsies taken would decrease by 60% with minimal loss of accuracy. A negative spectroscopy result would exclude high grade dysplasia or cancer with an accuracy of >99.5%. These preliminary results show that elastic scattering spectroscopy has the potential to target conventional biopsies in Barrett's surveillance saving significant endoscopist and pathologist time with consequent financial savings. This technique now requires validation in prospective studies.
Article
Full-text available
Elastic scattering spectroscopy (ESS) may be used to detect high-grade dysplasia (HGD) or cancer in Barrett's esophagus (BE). When spectra are measured in vivo by a hand-held optical probe, variability among replicated spectra from the same site can hinder the development of a diagnostic model for cancer risk. An experiment was carried out on excised tissue to investigate how two potential sources of this variability, pressure and angle, influence spectral variability, and the results were compared with the variations observed in spectra collected in vivo from patients with Barrett's esophagus. A statistical method called error removal by orthogonal subtraction (EROS) was applied to model and remove this measurement variability, which accounted for 96.6% of the variation in the spectra, from the in vivo data. Its removal allowed the construction of a diagnostic model with specificity improved from 67% to 82% (with sensitivity fixed at 90%). The improvement was maintained in predictions on an independent in vivo data set. EROS works well as an effective pretreatment for Barrett's in vivo data by identifying measurement variability and ameliorating its effect. The procedure reduces the complexity and increases the accuracy and interpretability of the model for classification and detection of cancer risk in Barrett's esophagus.
Article
Objective: Clinical examination of the oral mucosa often leads to an uncertain diagnosis, and a supplementary biopsy with a histopathologic examination of the lesion is necessary to establish a definite diagnosis. However, the site for the biopsy is a subjective choice that sometimes raises doubts about its representativeness. So far, no simple and reliable method is available for selecting the most appropriate area for biopsy. Study Design: In a prospective study, we performed direct oral microscopy (oral application of the colposcopy technique used in gynecology) in 35 patients with various clinical diagnoses, such as leukoplakia, oral lichenoid lesions, or suspected malignancy. First, the oral mucosa was examined with direct microscopy, and the most representative site, according to colposcopic criteria, was selected. Then, the mucosa was clinically inspected by an independent examiner. The best site for biopsy according to clinical criteria was noted, and any difference in biopsy sites was recorded. Biopsy specimens were taken from 2 of these sites. Results: Twenty-nine patients (83%) showed changes in the vascular picture on microscopy, according to the colposcopy criteria. In 14 patients (40%), the biopsy sites identified by direct oral microscopy showed more advanced histologic signs than those selected by routine clinical examination (0.01 < P ≤ .05). Four patients (11%) had more advanced histologic signs in the biopsy samples, as identified during routine clinical examination. In 17 patients (49%), we found no differences between the biopsy specimens. Conclusion: Direct oral microscopy of mucosal lesions seems to offer advantages in selecting more representative sites for biopsy than routine clinical examination alone. (Oral Surg Oral Med Oral Pathol Oral Radiol Endod 2000;90:164-70)
Article
Background and Objectives Optical coherence tomography (OCT) is a depth resolved imaging modality that may aid in identifying sun damaged skin and the precancerous condition actinic keratosis (AK).Study Design/Materials and MethodsOCT images were acquired of 112 patients at 2 sun protected and 2 sun exposed sites, with a subsequent biopsy. Each site received a dermatological evaluation, a histological diagnosis, and a solar elastosis (SE) score. OCT images were examined visually and statistically analyzed.ResultsCharacteristic OCT image features were identified of sun protected, undiseased, sun damaged, and AK skin. A statistically significant difference (P<0.0001) between the average attenuation values of skin with minimal and severe solar elastosis was observed. Significant differences (P<0.0001) were also found between undiseased skin and AK using a gradient analysis. Using image features, AK could be distinguished from undiseased skin with 86% sensitivity and 83% specificity.ConclusionOCT has the potential to guide biopsies and provide non-invasive measures of skin sun damage and disease state, possibly increasing efficiency of chemopreventive agent trials. Lesers Surg. Med. 39:687–695, 2007. © 2007 Wiley-Liss, Inc.
Article
Elastic scattering spectroscopy (ESS) has been shown to be accurate in the identification of abnormalities of soft tissue. These include ischemia and inflammation, pre-cancer and cancer. The aim of this study was to compare findings of ESS with gold standard histopathology in patients with various skin lesions. Seventy-three patients with clinically suspicious facial skin lesions were included. Those lesions with the surrounding innocuous skin were interrogated by ESS, biopsies were taken and examined histopathologically; the results were then compared. The preliminary analysis showed obvious spectral differences between normal and pathological skin. Spectral differences were identified when comparing benign skin conditions to malignant ones. Spectral differences were identified between basal cell carcinomas and other skin lesions. This preliminary study shows that ESS can distinguish between normal, benign and malignant skin conditions.
Article
Raman spectroscopy is a non-invasive optical technique, which can assess molecular structures and conformations within biological tissue. The probability of Raman scattering is inherently low such that previous clinical applications of Raman spectroscopy have been limited by long data acquisition times. We have developed a rapid real-time Raman spectrometer system with measurement times of less than 1 second, paving the way for clinical application. In this presentation, we report preliminary clinical results for this real-time Raman system. To date 289 skin cancers and benign skin lesions have been measured. Using partial least squares regression and linear discriminant analysis to analyze the Raman spectra we found that skin cancers could be well differentiated from benign skin lesions (sensitivity 91% and specificity 75%) and malignant melanoma from benign pigmented lesions (sensitivity 97%, specificity 78%).
Article
Steady state fluorescence polarization spectra and time-resolved emission decay kinetics have been measured in vitro from malignant and normal rat kidney tissue. The degrees of polarization and emission lifetimes from the cancerous and normal systems are different. The spectroscopic differences are attributed to environmental transformations local to the native flavin and porphyrin fluorophors' binding sites.