Histopathological Spectrum of Cutaneous Basal Cell Carcinoma- An 11 Year Retrospective Study in a Tertiary Care Hospital in Southern Karnataka

Introduction: Basal Cell Carcinoma (BCC) is a slow growing, locally invasive, malignant skin tumour with increasing incidence in recent decades. Various histological subtypes of BCC have been described which include nodular, superficial, adenoid, keratotic, basosquamous, and morpheiform. Aim: To analyse the clinical data of patients with BCC and the histomorphological spectrum of BCCs in a population of Southern Karnataka. Materials and Methods: This was an 11 year retrospective descriptive observational study of all histologically confirmed BCCs diagnosed in the Department of Pathology in a tertiary care centre in Southern Karnataka from January 2010 to January 2021. Detailed clinical data of 64 patients including age, gender, clinical diagnosis and anatomic location were analysed. Results: The maximum number of BCCs occurred in the sixth decade with a slight female preponderance. Head and neck lesions were the most common and uncommon sites noted included the vulva and axilla. Most cases presented as an irregular plaque followed by presentation as an ulcerative lesion. Pigmentation was noted in 18 (28%) cases clinically. Majority of patients (63/64 or 98.4%) had a single lesion. Histological types included nodular, superficial, adenoid, basosquamous and BCC with sebaceous differentiation. Nodular BCC was the most commonly encountered type in our setting, followed by superficial BCC. Only one case of basosquamous carcinoma showed evidence of metastasis to lymph nodes. Conclusion: Histological evaluation of BCC is of paramount importance not only to establish the diagnosis but also to predict behaviour and risk of recurrence. In addition to the diagnosis, pathologist should also describe subtypes of the tumour which has a prognostic implication. This study reveals the morphological spectrum of BCC in the population of southern Karnataka and reveals significant patterns in anatomical distribution of BCC. It also highlights a significant percentage of BCCs presenting as pigmented lesions in the Indian population.