Vulval squamous cell carcinoma arising from hidradenitis suppurrativa.

A 47- year-old woman developed a rapidly enlarging vulvar mass. Although the clinical appearance suggested malignancy, its lack of atypia and invasion on initial superficial biopsy delayed the pathological diagnosis. It was not until a large incisional biopsy was performed that showed the diagnosis of verrucous squamous cell carcinoma (VSCC) involving pre-existing sinuses of hidradenitis suppurativa (HS). VSCC arising in HS is very rare and often leads to death in published cases. This case demonstrates the challenge in pathological diagnosis of this condition which impacted time to treatment.