Difference in histological subtypes of basal cell carcinoma according to age, gender, location, mitotic activity and association with solar keratoses

Background and aim: Basal cell carcinoma (BCC) is the most common skin cancer in white-skin populations. Recent studies suggest that BCC is not a single entity and different histological subtypes show different clinical behavior and might have different etiology. The aim of this study was to assess differences in age, sex, site of distribution and proliferative activity in histological subtypes of BCC. In addition association of BCC with solar keratoses is assessed.Materials and methods: We studied 299 cases of BCC from the archives of department of pathology, Mashad University of Medical Sciences in a three-year period. Clinical data were recorded and histological slides were rewiewed to confirm the diagnosis and histological subtypes. Results: We recorded 345 BCC in 299 patients with mean age of 59.2 years. 70.8% of patients were male and 29.2% were female. Ninety-four percent of lesions were located in head and neck. Solid pattern of BCC was the most frequent subtype. In superficial and micronodular subtypes, patients were younger and the oldest patients had basosquamous BCC. Adenoid BCC had the most mitotic activity. In 22.2% of cases association with solar keratoses were observed.Conclusion: This study showed difference in age, sex, site of tumor, and proliferative activity in various histological subtypes of BCC that might represent different etiologic factors in different subtypes.