Dermoscopy Improves Accuracy of Primary Care Physicians to Triage Lesions Suggestive of Skin Cancer
ABSTRACT Primary care physicians (PCPs) constitute an appropriate target for new interventions and educational campaigns designed to increase skin cancer screening and prevention. The aim of this randomized study was to determine whether the adjunct of dermoscopy to the standard clinical examination improves the accuracy of PCPs to triage lesions suggestive of skin cancer.
PCPs in Barcelona, Spain, and Naples, Italy, were given a 1-day training course in skin cancer detection and dermoscopic evaluation, and were randomly assigned to the dermoscopy evaluation arm or naked-eye evaluation arm. During a 16-month period, 73 physicians evaluated 2,522 patients with skin lesions who attended their clinics and scored individual lesions as benign or suggestive of skin cancer. All patients were re-evaluated by expert dermatologists at clinics for pigmented lesions. Referral accuracy of both PCP groups was calculated by their scores, which were compared to those tabulated for dermatologists.
Referral sensitivity, specificity, and positive and negative predictive values were 54.1%, 71.3%, 11.3%, and 95.8%, respectively, in the naked-eye arm, and 79.2%, 71.8%, 16.1%, and 98.1%, respectively, in the dermoscopy arm. Significant differences were found in terms of sensitivity and negative predictive value (P = .002 and P = .004, respectively). Histopathologic examination of equivocal lesions revealed 23 malignant skin tumors missed by PCPs performing naked-eye observation and only six by PCPs using dermoscopy (P = .002).
The use of dermoscopy improves the ability of PCPs to triage lesions suggestive of skin cancer without increasing the number of unnecessary expert consultations.
- SourceAvailable from: Rafael Garcia
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- "In some developed countries it is the more frequent cancer in women younger than 29 years and men between 30 and 35 years. Melanoma is often lethal but can usually be cured if diagnosed early . Therefore, early detection is important to increase the chance for successful treatment . "
ABSTRACT: This paper proposes a new color correction pipeline to improve the dermoscopy image quality. Images acquired with different cameras or different dermoscopes often present problems of faithful color reproduction. The colors of these images are often far different the ones observed with the naked eye, and usually vary from one camera to another. Nowadays digital cameras perform "black-box" color corrections taking into account the color temperature of the imaged scene, which may result in some cases in unrealistic color rendering. For this reason, it is necessary to calibrate the imaging system (the camera and a specific dermoscope). The calibration process requires finding a relationship between a device-dependent color space and a standard color space depending only on the human eye. This relation is obtained acquiring known color patches of a color checker and relating them with the pixel values obtained by the camera. In our approach we model the color calibration problem using a new formulation that takes into account the spectral distribution of the dermoscope lighting system and conveys a solution for both RAW and JPEG images. When comparing images captured with different cameras, this new method improves the results between 0.1 and 0.9 ΔE with respect to previous approaches.Computerized medical imaging and graphics: the official journal of the Computerized Medical Imaging Society 04/2011; 35(7-8):646-52. DOI:10.1016/j.compmedimag.2011.03.006 · 1.22 Impact Factor
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- "New approaches are required to improve GPs' assessment of pigmented skin lesions. Dermoscopy has been shown to improve the diagnostic accuracy for melanoma in the specialist setting  and in two randomised controlled trials in general practice [13,14]. However, dermoscopy is a relatively time-consuming technique to learn; in a recent trial of dermoscopy and digital monitoring Australian GPs required up to 30 hours of internet-based learning to acquire adequate skills and only 63% of those trained actually recruited patients into the trial. "
ABSTRACT: Diagnosing pigmented skin lesions in general practice is challenging. SIAscopy has been shown to increase diagnostic accuracy for melanoma in referred populations. We aimed to develop and validate a scoring system for SIAscopic diagnosis of pigmented lesions in primary care. This study was conducted in two consecutive settings in the UK and Australia, and occurred in three stages: 1) Development of the primary care scoring algorithm (PCSA) on a sub-set of lesions from the UK sample; 2) Validation of the PCSA on a different sub-set of lesions from the same UK sample; 3) Validation of the PCSA on a new set of lesions from an Australian primary care population. Patients presenting with a pigmented lesion were recruited from 6 general practices in the UK and 2 primary care skin cancer clinics in Australia. The following data were obtained for each lesion: clinical history; SIAscan; digital photograph; and digital dermoscopy. SIAscans were interpreted by an expert and validated against histopathology where possible, or expert clinical review of all available data for each lesion. A total of 858 patients with 1,211 lesions were recruited. Most lesions were benign naevi (64.8%) or seborrhoeic keratoses (22.1%); 1.2% were melanoma. The original SIAscopic diagnostic algorithm did not perform well because of the higher prevalence of seborrhoeic keratoses and haemangiomas seen in primary care. A primary care scoring algorithm (PCSA) was developed to account for this. In the UK sample the PCSA had the following characteristics for the diagnosis of 'suspicious': sensitivity 0.50 (0.18-0.81); specificity 0.84 (0.78-0.88); PPV 0.09 (0.03-0.22); NPV 0.98 (0.95-0.99). In the Australian sample the PCSA had the following characteristics for the diagnosis of 'suspicious': sensitivity 0.44 (0.32-0.58); specificity 0.95 (0.93-0.97); PPV 0.52 (0.38-0.66); NPV 0.95 (0.92-0.96). In an analysis of lesions for which histological diagnosis was available (n = 111), the PCSA had a significantly greater Area Under the Curve than the 7-point checklist for the diagnosis of melanoma (0.83; 95% CI 0.71-0.95 versus 0.61; 95% CI 0.44-0.78; p = 0.02 for difference). The PCSA could have a useful role in improving primary care management of pigmented skin lesions. Further work is needed to develop and validate the PCSA in other primary care populations and to evaluate the cost-effectiveness of GP management of pigmented lesions using SIAscopy.BMC Dermatology 09/2010; 10(9):9. DOI:10.1186/1471-5945-10-9
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- "It has been recently claimed that dermoscopy is the conceptual and practical link between clinical dermatology (macrocosm) and dermatopathology (microcosm) , . Like clinical dermatology, dermoscopy works in parallel to the skin surface; like histopathology, it allows to visualize structures which could not be discernible by the naked eye. "
ABSTRACT: We tested the relevance of clinical information in the histopathologic evaluation of melanocytic skin neoplasm (MSN). Histopathologic specimens from 99 clinically atypical MSN were circulated among ten histopathologists; each case had clinical information available in a database with a five-step procedure (no information; age/sex/location; clinical diagnosis; clinical image; dermoscopic image); each step had a histopathologic diagnosis (D1 through D5); each diagnostic step had a level of diagnostic confidence (LDC) ranging from 1 (no diagnostic certainty) to 5 (absolute diagnostic certainty). The comparison of the LDC was employed with an analysis of variance (ANOVA) for repeated measures. In D1 (no information), 36/99 cases (36.3%) had unanimous diagnosis; in D5 (full information available), 51/99 cases (51.5%) had unanimous diagnosis (p for difference between proportions <0.001). The observer agreement expressed as kappa increased significantly from D1 to D5. The mean LDC linearly increased for each observer from D1 through D5 (p for linear trend <0.001). On average, each histopathologist changed his initial diagnosis in 7 cases (range: 2-23). Most diagnostic changes were in D2 (age/sex/location). The histopathologic criteria for the diagnosis of MSN can work as such, but the final histopathologic diagnosis is a clinically-aided interpretation. Clinical data sometimes reverse the initial histopathologic evaluation.PLoS ONE 06/2009; 4(4):e5375. DOI:10.1371/journal.pone.0005375 · 3.23 Impact Factor