Vulvar keratoacanthoma may be a malignant precursor: A case report and literature review

Keratoacanthoma is a relatively rare skin tumor, with vulvar keratoacanthoma being even more uncommon. Although the majority of keratoacanthomas exhibit a benign course, a subset of cases may show features of malignant potential, such as marginal invasion and recurrence.

An 82-year-old female presented with a rapidly growing exophytic lesion on the left vulva, measuring 1.5 cm in diameter, accompanied by pruritus. The lesion had been present for two months. The patient underwent vulvar mass excision, and postoperative pathology revealed squamous cell hyperplasia with glassy cytoplasm and no significant cellular atypia. The surgical margins were clear. Three years later, the tumor recurred with disordered growth.

In terms of histological and clinical presentation, keratoacanthoma may overlap with classical well-differentiated squamous cell carcinoma. In rare cases, certain atypical keratoacanthomas may exhibit intravascular and perineural invasion, along with lymph node metastasis. By sharing our treatment experience of a patient with recurrent vulvar keratoacanthoma following surgery, we aim to provide a cautionary perspective for the clinical management of such cases.