Squamous cell carcinoma over a nevus: a rare case.

Malignant melanoma and basal cell carcinoma are more common over a preexisting nevus. But squamous cell carcinoma over a nevus is a rare phenomenon. A 55-year-old male presented with a slow growing noduloulcerative lesion on a preexisting nevus over scalp. For that he had undergone excisional biopsy. Biopsy came out to be a squamous cell carcinoma with lateral margin positive for tumor. So postoperative radiotherapy given by means of HDR brachytherapy. Now he is on follow-up.