Baseline comorbidities in a skin cancer prevention trial in Bangladesh.

BACKGROUND: Epidemiologic research suggests that increased cancer risk due to chronic arsenic exposure persists for several decades even after the exposure has terminated. Observational studies suggest that antioxidants exert a protective effect on arsenical skin lesions and cancers among those chronically exposed to arsenic through drinking water. This study reports on the design, methods and baseline analyses from the Bangladesh Vitamin E and Selenium Trial (BEST), a population-based chemoprevention study conducted among adults in Bangladesh with visible arsenic toxicity. MATERIALS AND METHODS: Bangladesh Vitamin E and Selenium Trial is a 2 × 2 full factorial, double-blind, randomized controlled trial of 7000 adults having manifest arsenical skin lesions evaluating the efficacy of 6-year supplementation with alpha-tocopherol (100 mg daily) and L-selenomethionine (200 µg daily) for the prevention of nonmelanoma skin cancer. RESULTS: In cross-sectional analyses, we observed significant associations of skin lesion severity with male gender (female prevalence odds ratio (POR) = 0.87; 95% CI = 0.79-0.96), older age (aged 36-45 years, POR = 1.27; 95% CI = 1.13-1.42; aged 46-55 years, POR = 1.44; 95% CI = 1.27-1.64 and aged 56-65 years, POR = 1.50; 95% CI = 1.26-1.78 compared with aged 25-35 years), hypertension (POR = 1.29; 95% CI = 1.08-1.55), diabetes (POR = 2.13; 95% CI = 1.32-3.46), asthma (POR = 1.55; 95% CI = 1.03-2.32) and peptic ulcer disease (POR = 1.20; 95% CI = 1.07-1.35). CONCLUSIONS: We report novel associations between arsenical skin lesions with several common chronic diseases. With the rapidly increasing burden of preventable cancers in developing countries, efficient and feasible chemoprevention study designs and approaches, such as employed in BEST, may prove both timely and potentially beneficial in conceiving cancer chemoprevention trials in Bangladesh and beyond.

Cutaneous Malignancy due to Arsenicosis in Bangladesh: 12-Year Study in Tertiary Level Hospital.

Bangladesh is grappling with the largest mass poisoning of a population in the world due to contamination of drinking water with naturally occurring inorganic arsenic. It is estimated that 75 million people of 59 (out of 64) districts are at risk of drinking contaminated water with arsenic above 50µg/L. Long term exposure to arsenic causes cancers, including skin, lung, and bladder. This is a randomized prospective study to see the prevalence of skin cancer from arsenic affected area of Bangladesh, as well as their variation by geographical area, age, gender, location on the body, and socioeconomic conditions, in outpatient department of plastic surgery unit of Bangabandhu Sheikh Mujib Medical University (BSMMU). A total of 960 patients with skin cancers comprised of 528 males and 432 females were selected for the study from January 2004 to December 2015. In this 12-year study, we found squamous cell carcinoma, basal cell carcinoma, melanoma, and Merkel cell carcinoma to be associated with the ingestion of arsenic contaminated ground water. This is a reflection of a small part of the total national scenario of devastating result of arsenic mediated cancer in terms of skin malignancy. This study will help the future researchers who are contemplating to work on arsenic induced health problem.