14 research outputs found
Fuzzy logic techniques for blotch feature evaluation in dermoscopy images
Blotches, also called structureless areas, are critical in differentiating malignant melanoma from benign lesions in dermoscopy skin lesion images. In this paper, fuzzy logic techniques are investigated for the automatic detection of blotch features for malignant melanoma discrimination. Four fuzzy sets representative of blotch size and relative and absolute blotch colors are used to extract blotchy areas from a set of dermoscopy skin lesion images. Five previously reported blotch features are computed from the extracted blotches as well as four new features. Using a neural network classifier, malignant melanoma discrimination results are optimized over the range of possible alpha-cuts and compared with results using crisp blotch features. Features computed from blotches using the fuzzy logic techniques based on three plane relative Color and blotch size yield the highest diagnostic accuracy of 81.2%. (C) 2008 Elsevier Ltd. All rights reserved
Hydrochlorothiazide and risk of melanoma subtypes
Background: Hydrochlorothiazide (HCTZ), a common diuretic known to be photosensitizing and previously associated with non-melanoma skin cancer, was recently reported to be associated with two melanoma subtypes, nodular and lentigo, among residents of Denmark. Our goal was to examine whether Danish findings could be replicated in a US cohort, using a similar study design and analysis. Methods: Among non-Hispanic White enrollees of Kaiser Permanente Northern California, we conducted an analysis of 9176 melanoma cases and 264 781 controls, matched on age, sex and time in health plan. We examined use of HCTZ prior to cancer diagnosis (cases) or comparable date for controls, categorized as never use, ever use and high use (≥50 000 mg). Electronic health records provided data on prescriptions, cancer diagnoses, and covariates. Conditional logistic regression was used to calculate odds ratios (ORs) and 95% confidence intervals (CIs), adjusted for education, income and number of dermatology, internal medicine and urgent care visits. Results: We observed a small increase in risk of melanoma, all types combined, associated with high use (≥50 000 mg) of HCTZ (OR = 1.11, 95% CI 1.00–1.23) and no evidence of a dose–response. Risk was more elevated for lentigo subtype (OR = 1.57, 95% CI 1.01–2.42). The somewhat elevated risk for nodular subtype was not statistically significant (OR = 1.22, 95% CI 0.78–1.90). There was very little association of high use with the superficial spreading subtype (OR = 1.05, 95% CI 0.80–1.37). Conclusions: Our findings support a recent report of an association between high use of HCTZ and increased risk of the lentigo subtype of melanoma.</p
Head and Neck Non-Melanoma Skin Cancer Treated By Superficial X-Ray Therapy: An Analysis of 1021 Cases
To report a single-institutional experience with the use of Superficial X-Ray Therapy (SXRT) for head and neck non-melanoma skin cancer (N-MSC) and to compare outcomes by prescribed fractionation schedules.The medical records of 597 patients with 1021 lesions (720 BCC, 242 SCC, 59 SCC in situ) treated with kilovoltage radiation from 1979-2013 were retrospectively reviewed. The majority of patients were treated according to 1 of 3 institutional protocols based on the discretion of the radiation oncologist: 1) 22 x 2.5 Gy; 2) 20 x 2.5 Gy; 3) 30 x 2.0 Gy. "T" stage at first presentation was as follows: Tis (59); T1 (765); T2 (175); T3 (6), T4 (9); Tx, (7). All patients were clinical N0 and M0 at presentation. Chi-square test was used to evaluate any potential association between variables. The Kaplan-Meier method was used to analyze survival with the Log Rank test used for comparison. A Cox Regression analysis was performed for multivariate analysis.The median follow up was 44 months. No significant difference was observed among the 3 prescribed fractionation schemes (p = 0.78) in terms of RTOG toxicity. There were no failures among SCC in situ, 37 local failures (23 BCC, 14 SCC), 5 regional failures (all SCC) and 2 distant failures (both SCC). For BCC, the 5-year LC was 96% and the 10-year LC was 94%. For SCC the corresponding rates of local control were 92% and 87%, respectively (p = 0.03). The use of >2.0 Gy daily was significantly associated with improved LC on multivariate analysis (HR: 0.17; CI 95%: 0.05-0.59).SXRT for N-MSC of the head and neck is well tolerated, achieves excellent local control, and should continue to be recommended in the management of this disease. Fractionation schedules using >2.0 Gy daily appear to be associated with improved LC
