CLINICAL AND PATHOLOGICAL CHARACTERISTICS OF BASAL CELL CARCINOMA ARISING FROM CHRONIC RADIATION DERMATITIS

Abstract

Clinical and histopathological features of basal cell carcinoma (BCC) may differ according to the type of carcinogen involved. BCC arising from radiotherapy treatment has high incidence and its clinical and histopathological features may be different from BCCs caused by other carcinogens. The aim of our study was to investigate any possible association between specific histopathological or clinical features and chronic radiation dermatitis as the cause of BCC. In this study, 87 patients with previous history of radiotherapy on the site of BCC (exposed) were selected as group A and matched with 87 other patients with BCC without such a history as group B (unexposed). The two groups were compared based on certain clinical features such as size, number and location of the tumors and also based on the histopathological features. In the exposed group, the most frequent histopathological type was pigmented solid type (73.5%), while in the unexposed group solid type (66.7%) was the most frequent feature. Multiple tumors were found in 86.2% of the exposed patients, while just 12.6% of the unexposed patients had multiple tumors. In the unexposed group, the face was the most frequent location (94.3%) and the mean size was 1 cm in diameter, while in the exposed group the most frequent location was the scalp and the mean size was 0.5 cm. BCCs arising on a background of radiation dermatitis are usually of pigmented solid type, multiple, smaller in size and normally are seen on the areas exposed to X-ray therapy.