Technology in cancer research & treatment (TECHNOL CANCER RES T )

Description

Technology in Cancer Research and Treatment welcomes manuscripts from active investigators involved in technologies devoted to early diagnosis, treatment, and palliation of cancer. The Journal will include both experimental and theoretical investigations. Among the topics that will be covered are MRI, including functional MRI, spiral CT, PET, optical spectroscopy, computer-aided reconstruction of tumors, computer-aided drug design, stereotactic radiosurgery, cryosurgery, brachytherapy, electroporation, photodynamic therapy, gene therapy, cancer vaccine, proteomics, and genomics, as they impact cancer research and treatment. Special emphasis will be given to non-invasive techniques. The Journal publishes original articles, express communications, opinion pieces, and timely reviews.

Impact factor 1.89

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    Impact factor
  • 5-year impact
    2.09
  • Cited half-life
    5.70
  • Immediacy index
    0.42
  • Eigenfactor
    0.00
  • Article influence
    0.59
  • Website
    Technology in Cancer Research and Treatment website
  • Other titles
    Technology in cancer research & treatment (Print), Technology in cancer research & treatment, Technology in cancer research and treatment
  • ISSN
    1533-0346
  • OCLC
    45625094
  • Material type
    Periodical, Internet resource
  • Document type
    Journal / Magazine / Newspaper, Internet Resource

Publications in this journal

  • Andrew J Wroe
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    ABSTRACT: To evaluate the scattered and secondary radiation fields present in and around a passive proton treatment nozzle. In addition, based on these initial tests and system reliability analysis, to develop, install, and evaluate a radiation shielding structure to protect sensitive electronics against single-event effects (SEE) and improve system reliability. Landauer Luxel+ dosimeters were used to evaluate the radiation field around one of the gantry-mounted passive proton delivery nozzles at Loma Linda University Medical Center's James M Slater, MD Proton Treatment and Research Center. These detectors use optically stimulated luminescence technology in conjunction with CR-39 to measure doses from X-ray, gamma, proton, beta, fast neutron, and thermal neutron radiation. The dosimeters were stationed at various positions around the gantry pit and attached to racks on the gantry itself to evaluate the dose to electronics. Wax shielding was also employed on some detectors to evaluate the usefulness of this material as a dose moderator. To create the scattered and secondary radiation field in the gantry enclosure, a polystyrene phantom was placed at isocenter and irradiated with 250 MeV protons to a dose of 1.3 kGy over 16 hours. Using the collected data as a baseline, a composite shielding structure was created and installed to shield electronics associated with the precision patient positioner. The effectiveness of this shielding structure was evaluated with Landauer Luxel+ dosimeters and the results correlated against system uptime. The measured dose equivalent ranged from 1 to 60 mSv, with proton/photon, thermal neutron, fast neutron, and overall dose equivalent evaluated. The position of the detector/electronics relative to both isocenter and also neutron-producing devices, such as the collimators and first and second scatterers, definitely had a bearing on the dose received. The addition of 1-inch-thick wax shielding decreased the fast neutron component by almost 50%, yet this yielded a corresponding average increase in thermal neutron dose of 150% as there was no Boron-10 component to capture thermal neutrons. Using these data as a reference, a shielding structure was designed and installed to minimize radiation to electronics associated with the patient positioner. The installed shielding reduced the total dose experienced by these electronics by a factor of 5 while additionally reducing the fast and thermal neutron doses by a factor of 7 and 14, respectively. The reduction in radiation dose corresponded with a reduction of SEE-related downtime of this equipment from 16.5 hours to 2.5 hours over a 6-month reporting period. The data obtained in this study provided a baseline for radiation exposures experienced by gantry- and pit-mounted electronic systems. It also demonstrated and evaluated a shielding structure design that can be retrofitted to existing electronic system installations. It is expected that this study will benefit future upgrades and facility designs by identifying mechanisms that may minimize radiation dose to installed electronics, thus improving facility uptime. © The Author(s) 2015.
    Technology in cancer research & treatment 01/2015;
  • Yehoshua Socol, James S Welsh
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    ABSTRACT: Computed tomography (CT) scans are of high clinical value as a diagnostic technique, and new applications continue to be identified. However, their application is challenged by emerging concerns regarding carcinogenesis from their radiation. Recent articles made a significant contribution to the above-mentioned concerns by reporting evidence for direct association of the radiation from CT scans with cancer. Such interpretation of the data has already been criticized; there is the possibility of reverse causation due to confounding factors. Nevertheless, such work has had a high impact, with one article being cited more than 300 times from the Web of Science Core Collection within 2 years. However, the data points on cancer relative risk versus CT dose in that article fit straight lines corresponding to the linear no-threshold hypothesis suspiciously well. Here, by applying rigorous statistical analysis, it is shown that the probability of the fit truly being that good or better is only 2%. The results of such studies therefore appear "too good to be true" and the credibility of their conclusions must be questioned. © The Author(s) 2015.
    Technology in cancer research & treatment 01/2015;
  • Kyung Hwan Kim, Byoung Chul Cho, Chang Geol Lee, Hye Ryun Kim, Yang Gun Suh, Jun Won Kim, Chihwan Choi, Jong Geal Baek, Jaeho Cho
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    ABSTRACT: In this study, the volume response and treatment outcome after hippocampus-sparing whole-brain radiotherapy (HS-WBRT) with simultaneous integrated boost (SIB) using tomotherapy were evaluated. Patients with primary lung adenocarcinoma and multiple brain metastases who had a Karnofsky performance status ≥70 and exhibited well-controlled extracranial disease were treated. The prescribed dose was administered in 10 to 14 fractions as 25 to 28 Gy to whole-brain parenchyma, as 40 to 48 Gy to the gross metastatic lesion, and as 30 to 42 Gy to a 5-mm margin to the metastatic lesion. Double-dose gadolinium contrast-enhanced magnetic resonance imaging at 1-mm slice thickness was performed before treatment and at 1, 4, and 7 months posttreatment. The tumor volume reduction ratio was calculated for each follow-up. Between July 2011 and September 2012, 11 patients with 70 lesions were included in this analysis. The median number of lesions per patient was 4 (range, 2-15). The median initial tumor volume was 0.235 cm(3) (range, 0.020-10.140 cm(3)). The treatment plans were evaluated regarding conformation number (CN), target coverage (TC), and homogeneity index (HI). The median follow-up duration was 14 months (range, 3-25 months) and the 1-year intracranial control rate was 67%. The tumor volume reduction was most prominent during the first month with a median reduction rate of 0.717 (range, -0.190 to 1.000). Complete remission was seen in 22 (33%) lesions, and 45 (64%) lesions showed more than 65% reduction in tumor volume. The CN, TC, and HI values were comparable to that of previous studies, and the mean hippocampal dose was 13.65 Gy. No treatment breaks or ≥G3 acute toxicities were observed during or after treatment. The HS-WBRT with SIB in patients with multiple brain metastases was effective and feasible for volume reduction and showed excellent intracranial control. © The Author(s) 2015.
    Technology in cancer research & treatment 01/2015;
  • Jinbao Guo, Bin Wang, Zhongxue Fu, Jinlai Wei, Weidong Lu
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    ABSTRACT: Hypoxia microenvironment, as a major feature of solid tumors, increases tumors progression and metastasis. To research whether hypoxia influences the epithelial-mesenchymal transition (EMT) and cancer stem cells (CSCs) of gastric cancer cells and their cell biological behaviors. Human gastric cancer cell lines BGC823 and SGC7901 were cultivated in different oxygen tensions for proliferation, colony formation, soft agar formation, migration, and invasion analyses. Markers of EMT (E-cadherin, N-cadherin, Vimentin, and Snail) and markers of CSCs (Sox2, Oct4, and Bmi1) were investigated by real-time polymerase chain reaction, Western blotting, and immunofluorescent analysis. Cultivated at hypoxic condition, BGC823 and SGC7901 cells morphology began to change significantly. The cells pretreated under hypoxia grew faster than those cells always cultivated in normoxia. Meanwhile, hypoxia pretreatment dramatically promoted cell proliferation, migration and invasion, and increased capability of colony and soft agar colony formation. Furthermore, under hypoxia, E-cadherin decreased and N-cadherin, Vimentin, Snail, Sox2, Oct4, and Bmi1 increased both on the level of messenger RNA and protein. We drew a conclusion that the hypoxic microenvironment induced EMT, upgraded stem-like properties of gastric cancer cells, promoted invasion and metastasis, and behaved more malignantly. © The Author(s) 2015.
    Technology in cancer research & treatment 01/2015;
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    ABSTRACT: Radiochromic EBT3 film is gaining acceptance as a valuable dosimetry system for high-energy photon beams. The advantages of these films over other dosimetry systems are low spectral sensitivity and high spatial resolution. The aim of this study was to validate EBT3 film as a dosimeter for machine and treatment quality assurance (QA) of a 50-kV radiotherapy unit. Absolute and relative doses were acquired using EBT3 GafChromic films and compared to a parallel-plate ionization chamber (IC), the standard IC for low-energy X-rays. EBT3 was also used to evaluate beam profiles and output factors. Two films above each other, mimicking the clinical situation of a dosimeter on top of the skin, were simultaneously irradiated to evaluate EBT3 as in vivo dosimeter. All films were irradiated for 3 minutes, which corresponds with a surface dose of 3.25 ± 0.07 Gy. A fifth-order polynomial function was found to be the best fit for the calibration curves. Good agreement between IC and EBT3 was found for absolute (0.92% for green and red color channels) and relative (1.2% and 1.0% for green and red color channels, respectively) dosimetry. Output factors for IC and EBT3 were comparable within 2.04% and 1.02% for the green and red color channels, respectively. Flatness and symmetry at the surface were within 2%. By applying film as in vivo dosimeter, an absorption of 4.70% needs to be taken into account with respect to the surface dose. EBT3 GafChromic film is a feasible and valuable QA and dosimetry tool for a 50-kV radiotherapy unit. EBT3 can be used for absolute and relative dosimetry, measurement of output factors and beam profiles. In vivo patient-specific QA can also be performed if one corrects for the dose absorption of the film. © The Author(s) 2015.
    Technology in cancer research & treatment 01/2015;
  • Shankar Siva, Thomas Devereux, David L Ball, Michael P MacManus, Nicholas Hardcastle, Tomas Kron, Mathias Bressel, Farshad Foroudi, Nikki Plumridge, Daniel Steinfort, Mark Shaw, Jason Callahan, Rodney J Hicks, Michael S Hofman
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    ABSTRACT: Ga-68-macroaggregated albumin ((68)Ga-perfusion) positron emission tomography/computed tomography (PET/CT) is a novel imaging technique for the assessment of functional lung volumes. The purpose of this study was to use this imaging technique for functional adaptation of definitive radiotherapy plans in patients with non-small cell lung cancer (NSCLC). This was a prospective clinical trial of patients with NSCLC who received definitive 3-dimensional (3D) conformal radiotherapy to 60 Gy in 30 fx and underwent pretreatment respiratory-gated (4-dimensional [4D]) perfusion PET/CT. The "perfused" lung volume was defined as all lung parenchyma taking up radiotracer, and the "well-perfused" lung volume was contoured using a visually adapted threshold of 30% maximum standardized uptake value (SUVmax). Alternate 3D conformal plans were subsequently created and optimized to avoid perfused and well-perfused lung volumes. Functional dose volumetrics were compared using mean lung dose (MLD), V5 (volume receiving 5 Gy or more), V10, V20, V30, V40, V50, and V60 parameters. Fourteen consecutive patients had alternate radiotherapy plans created based on functional lung volumes. When considering the original treatment plan, the dose to perfused and well-perfused functional lung volumes was similar to that of the conventional anatomical lung volumes with an average MLD of 12.15, 12.67, and 12.11 Gy, respectively. Plans optimized for well-perfused lung improved functional V30, V40, V50, and V60 metrics (all P values <.05). The functional MLD of well-perfused lung was improved by a median of 0.86 Gy, P < .01. However, plans optimized for perfused lung only showed significant improvement in the functional V60 dose parameter (median 1.00%, P = .04) but at a detriment of a worse functional V5 (median 3.33%, P = .05). This study demonstrates proof of principle that 4D-perfusion PET/CT may enable functional lung avoidance during treatment planning of patients with NSCLC. Radiotherapy plans adapted to well-perfused but not perfused functional lung volumes allow for reduction in dose to functional lung using 3D conformal radiotherapy. © The Author(s) 2015.
    Technology in cancer research & treatment 01/2015;
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    ABSTRACT: This study quantifies the setup uncertainties to optimize the planning target volume (PTV) margin based on daily image guidance, its dosimetric impact, and radiobiological implication for intensity-modulated radiation therapy (IMRT) in head and neck cancer. Ten patients were retrospectively chosen who had been treated with IMRT and with daily image-guided radiation therapy (IGRT). The daily setup errors of the 10 patients from on-board imaging for the entire treatment were analyzed. Planning target volumes were generated by expanding the clinical target volumes (CTVs) with 0 to 10 mm margins. The IMRT plans with the same dose-volume constraints were created in an Eclipse treatment planning system. The effect of volume expansion was analyzed with biological indices such as tumor control probability, normal tissue complication probability (NTCP), and equivalent uniform dose. Analysis of 906 daily setup corrections using daily IGRT showed that 98% of the daily setups are within +/-5 mm. The relative increase in PTV-CTV volume from 0 to 10 mm margins provides nearly 4-fold volume increase and is linearly related to monitor unit (MU). The increase in MU is about 5%/mm margin increase. The relative increase in NTCP of parotids from 5 to 10 mm margins is 3.2 +/- 1.15. Increase in PTV margin increases extra tissue volume with a corresponding increase in MU for treatment and NTCP values. Even a small margin increase (eg, 1 mm) may result in increase of more than 20% in relative extra volume and 15% in NTCP value of organs at risk (OARs). With image guidance, the setup uncertainty could be achieved within +/-5 mm for 98% of the treatments, and a margin <5 mm for PTV may seem desirable to reduce the extra tissue irradiated, but at the expense of a more demanding setup accuracy.
    Technology in cancer research & treatment 11/2014;
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    ABSTRACT: Raman spectroscopy has been widely used in biomedical research and clinical diagnostics. It possesses great potentials for the analysis of biochemical processes in cell studies. In this article, the surface-enhanced Raman spectroscopy (SERS) of normal and cancerous liver cells incubated with SERS active substrates (gold nanoparticle) was measured using confocal Raman microspectroscopy technology. The chemical components of the cells were analyzed through statistical methods for the SERS spectrum. Both the relative intensity ratio and principal component analysis (PCA) were used for distinguishing the normal liver cells (QSG-7701) from the hepatoma cells (SMMC-7721). The relative intensity ratio of the Raman spectra peaks such as I937/I1209, I1276/I1308, I1342/I1375, and I1402/I1435 was set as the judge boundary, and the sensitivity and the specificity using PCA method were calculated. The results indicated that the surface-enhanced Raman spectrum could provide the chemical information for distinguishing the normal cells from the cancerous liver cells and demonstrated that SERS technology possessed the possible applied potential for the diagnosis of liver cancer. © The Author(s) 2014.
    Technology in cancer research & treatment 11/2014;
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    ABSTRACT: The objective of this study is to compare the new and conventional tomotherapy treatment techniques and to evaluate dosimetric differences between them. A dosimetric analysis was performed by comparing planning target volume (PTV) median dose, 95% of PTV dose coverage, Paddick conformity index (CI), homogeneity index (HI), whole-body integral dose, and OAR median doses. The beam on time (BOT) and the effect of different jaw sizes and pitch values was studied. The study results indicated that the PTV dose coverage for all the techniques was comparable. Treatment plans using dynamic jaw reduced OAR doses to structures located at the treatment field edge compared to fixed jaw plans. The HT-3DCRT plans resulted in higher OAR doses to kidney, liver, and lung compared to the other techniques, and TD-IMRT provided the best dose sparing to liver compared to other techniques. Whole-body integral dose differences were found to be insignificant among the techniques. BOT was found to be higher for fixed jaw treatment plan compared to dynamic jaw plan and comparable between all treatment techniques with 5-cm dynamic jaw. In studying effect of jaw size, better OAR sparing and HI were found for 2.5-cm jaw but at the expense of doubling of BOT as compared to 5-cm jaw. There was no significant improvement found in OAR sparing when the pitch value was increased. Increasing the pitch from 0.2 to 0.43, the CI was improved, HI improved only for 5-cm jaw size, and BOT decreased to approximately half of its original time.
    Technology in cancer research & treatment 11/2014;
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    ABSTRACT: Photodynamic therapy (PDT) is a relatively new modality for anticancer treatment and although the interest has increased greatly in the recent years, it is still far from clinical routine. As PDT consists of administering a nontoxic photosensitizing chemical and subsequently illuminating the tumor with visible light, the treatment is not subject to dose-limiting toxicity, which is the case for established anticancer treatments like radiation therapy or chemotherapy. This makes PDT an attractive adjuvant therapy in a combined modality treatment regimen, as PDT provides an antitumor immune response through its ability to elicit the release of damage-associated molecular patterns and tumor antigens, thus providing an increased antitumor efficacy, potentially without increasing the risk of treatment-related toxicity. There is great interest in the elicited immune response after PDT and the potential of combining PDT with other forms of treatment to provide potent antitumor vaccines. This review summarizes recent studies investigating PDT as part of combined modality treatment, hopefully providing an accessible overview of the current knowledge that may act as a basis for new ideas or systematic evaluations of already promising results.
    Technology in cancer research & treatment 11/2014;
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    ABSTRACT: This article proposes quantitative analysis tools and digital phantoms to quantify intrinsic errors of deformable image registration (DIR) systems and establish quality assurance (QA) procedures for clinical use of DIR systems utilizing local and global error analysis methods with clinically realistic digital image phantoms. Landmark-based image registration verifications are suitable only for images with significant feature points. To address this shortfall, we adapted a deformation vector field (DVF) comparison approach with new analysis techniques to quantify the results. Digital image phantoms are derived from data sets of actual patient images (a reference image set, R, a test image set, T). Image sets from the same patient taken at different times are registered with deformable methods producing a reference DVFref. Applying DVFref to the original reference image deforms T into a new image R'. The data set, R', T, and DVFref, is from a realistic truth set and therefore can be used to analyze any DIR system and expose intrinsic errors by comparing DVFref and DVFtest. For quantitative error analysis, calculating and delineating differences between DVFs, 2 methods were used, (1) a local error analysis tool that displays deformation error magnitudes with color mapping on each image slice and (2) a global error analysis tool that calculates a deformation error histogram, which describes a cumulative probability function of errors for each anatomical structure. Three digital image phantoms were generated from three patients with a head and neck, a lung and a liver cancer. The DIR QA was evaluated using the case with head and neck.
    Technology in cancer research & treatment 10/2014;
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    ABSTRACT: Intensity-modulated radiotherapy (IMRT) potentially leads to a more favorite dose distribution compared to 3-dimensional or conventional tangential radiotherapy (RT) for breast cancer after conservative surgery or mastectomy. The aim of this study was to compare dosimetric parameters of the planning target volume (PTV) and organs at risk (OARs) among helical tomotherapy (HT), inverse-planned IMRT (IP-IMRT), and forward-planned field in field (FP-FIF) IMRT techniques after breast-conserving surgery. Computed tomography scans from 20 patients (12 left sided and 8 right sided) previously treated with T1N0 carcinoma were selected for this dosimetric planning study. We designed HT, IP-IMRT, and FP-FIF plans for each patient. Plans were compared according to dose-volume histogram analysis in terms of PTV homogeneity and conformity indices (HI and CI) as well as OARs dose and volume parameters. Both HI and CI of the PTV showed statistically significant difference among IP-IMRT, FP-FIF, and HT with those of HT were best (P < .05). Compared to FP-FIF, IP-IMRT showed smaller exposed volumes of ipsilateral lung, heart, contralateral lung, and breast, while HT indicated smaller exposed volumes of ipsilateral lung but larger exposed volumes of contralateral lung and breast as well as heart. In addition, HT demonstrated an increase in exposed volume of ipsilateral lung (except for fraction of lung volume receiving >30 Gy and 20 Gy), heart, contralateral lung, and breast compared with IP-IMRT. For breast cancer radiotherapy (RT) after conservative surgery, HT provides better dose homogeneity and conformity of PTV compared to IP-IMRT and FP-FIF techniques, especially for patients with supraclavicular lymph nodes involved. Meanwhile, HT decreases the OAR volumes receiving higher doses with an increase in the volumes receiving low doses, which is known to lead to an increased rate of radiation-induced secondary malignancies. Hence, composite factors including dosimetric advantage, clinical effect, and economic burden should be taken into comprehensive consideration when choosing an RT technique in clinical practice.
    Technology in cancer research & treatment 10/2014;
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    ABSTRACT: In recent years, over 1000 reports have been published on the association between hepatic diseases and gene mutations which may result in pathogenic amino acids. Most of the studies focus on the hepatocellular carcinoma (HCC). The aim was to systematically examine the published literature on the association between the mutations of arginine, serine, and threonine and hepatic diseases, particularly HCC. The Biosciences information service database was systematically searched before July 10, 2012. Of the initially selected 471 publications, 112 articles were included in this study. Meta-analyses were conducted for 3 amino acids. Risk ratios were used to analyze the association between amino acids and liver diseases. We analyze the literature on the association between gene mutations and hepatic diseases, especially in patients with HCC. Full-text articles were analyzed by 4 independent researchers. Some amino acid mutations were found only in people with liver diseases-not in the general population. Arginine and threonine mutations occurred more frequently in patients with hepatic diseases, compared to the normal population. There is a statistically significant association between arginine mutations and the risk of HCC and serine mutations and the risk of HCC.
    Technology in cancer research & treatment 09/2014;
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    ABSTRACT: Radiographic changes occur in over half of patients treated with stereotactic body radiotherapy (SBRT) to the lung, correlating histopathologically with injury. We quantified radiographic density changes (ie, fibrosis) at 3, 6, and 12 months and investigated the relationship between these volumes and clinical and dosimetric parameters. The study population consisted of patients treated with SBRT to the lung for stage I primary lung cancers (n = 39) or oligometastatic lesions (n = 17). Fractionation schemes included 3 fractions of 12, 14, or 18 gray (Gy) and 4 fractions of 12 or 12.5 Gy prescribed to cover 95% of the planning target volume (PTV). Planning computed tomography (CT) scans were rigidly registered to follow-up CT scans obtained at intervals of 3, 6, and 12 months. Fibrotic volumes were contoured on the follow-up scans. Associations between the volume of fibrosis and clinical and dosimetric parameters were investigated using univariate linear regression. Scans were available for 65 and 47 lesions at 6 and 12 months, respectively. Age, years since quitting smoking, and GOLD Global Initiative for Chronic Obstructive Lung Disease score were significantly associated with increasing volume of fibrosis (P < .05). Total dose, dose per fraction, PTV, and volumetric parameters (V0-V55) were also significantly associated with increasing volumes of fibrosis (P < .01). For dosimetric parameters, the effect was largest for V55. Age, significant smoking history, and GOLD score were significantly associated with increasing volumes of fibrosis following SBRT. In a multivariate model adjusted for age and smoking history, V10 through V50 and PTV size remained significant predictors of fibrotic volume. Further, there is a strong dose-response relationship between the volume of lung exposed to a certain dose and the fibrotic volume. The predominant kinetic patterns of fibrosis demonstrate peaking fibrotic volumes at 6 and 12 months. These results provide insight for expectations of fibrosis after SBRT.
    Technology in cancer research & treatment 09/2014;
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    ABSTRACT: Magnetic resonance (MR)-based modalities aid breast cancer detection without exposure to ionizing radiation. Magnetic resonance imaging is very sensitive but costly and insufficiently specific. Molecular imaging through magnetic resonance spectroscopy (MRS) can provide information about key metabolites. Here, the measured/encoded time signals cannot be interpreted directly, necessitating mathematics for mapping to the more manageable frequency domain. Conventional applications of MRS are hampered by data analysis via the fast Fourier transform (FFT) and postprocessing by fitting techniques. Most in vivo MRS studies on breast cancer rely upon estimations of total choline (tCHO). These have yielded only incremental improvements in diagnostic accuracy. In vitro studies reveal richer metabolic information for identifying breast cancer, particularly in closely overlapping components of tCHO. Among these are phosphocholine (PC), a marker of malignant transformation of the breast. The FFT cannot assess these congested spectral components. This can be done by the fast Padé transform (FPT), a high-resolution, quantification-equipped method, which we presently apply to noisy MRS time signals consistent with those encoded in breast cancer. The FPT unequivocally and robustly extracted the concentrations of all physical metabolites, including PC. In sharp contrast, the FFT produced a rough envelope spectrum with a few distorted peaks and key metabolites absent altogether. As such, the FFT has poor resolution for these typical MRS time signals from breast cancer. Hence, based on Fourier-estimated envelope spectra, tCHO estimates are unreliable. Using even truncated time signals, the FPT clearly distinguishes noise from true metabolites whose concentrations are accurately extracted. The high resolution of the FPT translates directly into shortened examination time of the patient. These capabilities strongly suggest that by applying the FPT to time signals encoded in vivo from the breast, MRS will, at last, fulfill its potential to become a clinically reliable, cost-effective method for breast cancer detection, including screening/surveillance.
    Technology in cancer research & treatment 09/2014;
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    ABSTRACT: We describe the rationale and implementation of a method for analyzing in-room positron emission tomography (PET) data to verify the proton beam range. The method is based on analyzing distal PET surfaces after passive scattering proton beam delivery. Typically in vivo range verification is done by comparing measured and predicted PET distribution for a single activity level at a selected activity line along the beam passage. In the method presented here, we suggest using a middle point method based on dual PET activity levels to minimize the uncertainty due to local variations in the PET activity. Furthermore, we introduce 2-dimensional (2D) PET activity level surfaces based on 3-dimensional maps of the PET activities along the beam passage. This allows determining not only average range differences but also range difference distributions as well as root mean square deviations (RMSDs) for a more comprehensive range analysis. The method is demonstrated using data from 8 patients who were scanned with an in-room PET scanner. For each of the 8 patients, the average range difference was less than 5 mm and the RMSD was 4 to 11 mm between the measured and simulated PET activity level surfaces for single-field treatments. An ongoing protocol at our institution allows the use of a single field for patients being imaged for the PET range verification study at 1 fraction during their treatment course. Visualizing the range difference distributions using the PET surfaces offers a convenient visual verification of range uncertainties in 2D. Using the distal activity level surfaces of simulated and measured PET distributions at the middle of 25% and 50% activity level is a robust method for in vivo range verification.
    Technology in cancer research & treatment 09/2014;
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    ABSTRACT: To evaluate visibility, artifacts, and distortions of various commercial markers in magnetic resonance imaging (MRI), computer tomography (CT), and ultrasound imaging used for radiotherapy planning and treatment guidance.
    Technology in cancer research & treatment 09/2014;
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    ABSTRACT: Ovarian cancer is the most common cause of death among gynecological malignancies. We discuss different types of clinical and nonclinical features that are used to study and analyze the differences between benign and malignant ovarian tumors. Computer-aided diagnostic (CAD) systems of high accuracy are being developed as an initial test for ovarian tumor classification instead of biopsy, which is the current gold standard diagnostic test. We also discuss different aspects of developing a reliable CAD system for the automated classification of ovarian cancer into benign and malignant types. A brief description of the commonly used classifiers in ultrasound-based CAD systems is also given.
    Technology in cancer research & treatment 09/2014;