RESUMEN
A 52-year-old female presented with labial ulcer of 4-month duration. Examination showed 1 cm × 1 cm single superficial ulcer in the right labium majus. Excision was done, and histopathologic examination revealed surface ulceration and dermal invasion by epithelial neoplasm formed of biphasic proliferation of squamoid and gland-forming cells. Immunohistochemical staining with p63 showed nuclear staining of the squamoid nests and was negative in areas with glandular differentiation, while epithelial membrane antigen and carcinoembryonic antigen highlighted the glandular elements. The case was diagnosed as primary cutaneous adenosquamous carcinoma (ASC). ASC is an uncommon malignant cutaneous neoplasm that is more aggressive than conventional squamous cell carcinoma. There are a few reports of ASC that presented as an erythematous papule or plaque with a preference for the head, neck, or upper extremities. We report a novel case of vulval ASC presented as a superficial ulcer, which is considered a unique site, and its clinical presentation.