Keratoacanthoma of the Scalp Presenting as a Verrucous Growth: A Diagnostic Challenge

Abstract

Keratoacanthoma (KA) is a rapidly growing, low-grade skin tumor that mimics squamous cell carcinoma (SCC) clinically and histologically. Its presentation on the scalp is uncommon and may pose diagnostic challenges.We report a 59-year-old female with a 3-year history of a scalp lesion that became painful and ulcerated. Examination revealed a 4×3 cm exophytic ulceroproliferative swelling with regional lymphadenopathy. Initial biopsy suggested verruca vulgaris. However, wide local excision with histopathology confirmed keratoacanthoma. The patient recovered well postoperatively, with no recurrence on follow-up. KA can be difficult to distinguish from SCC both clinically and microscopically. Misdiagnosis may lead to overtreatment or undertreatment. Excisional biopsy remains critical for definitive diagnosis and it is crucial to give adequate margins.  This case highlights the importance of considering KA in the differential diagnosis of scalp lesions and reinforces surgical excision as both diagnostic and therapeutic.