Rippled Pattern Basal Cell Carcinoma - A Rare Variant with a Diagnostic Approach.

The rippled pattern of basal cell carcinoma (BCC) is a very uncommon variant and poses a diagnostic challenge. A 52-year-old male presented with an ulcerated lesion over the scalp for 8 years. The wedge biopsy of the lesion showed an infiltrating tumour in the upper dermis and mid-dermis with focal attachment with the epidermis. The tumour was arranged in a rippled pattern. The tumour cells were monomorphic with a round to oval nucleus, arranged parallelly with fine chromatin and inconspicuous nucleoli. Brisk mitosis, apoptotic bodies, and necrosis were noted. Immunohistochemically, the tumour cells were positive for p63; focally positive for androgen receptor, Bcl-2, and CD10; and negative for epithelial membrane antigen and CK20. We report this rare case of BCC because of its peculiar pattern, discuss the differential diagnoses, and review the clinicopathological features of reported cases.