Recurrent proliferating trichilemmal tumor of the vulva: a case report

Proliferating trichilemmal tumor (PTT) is a rare but morphologically distinct tumor that usually arises on the scalp of elderly women. It is composed of multiple cysts consisting of squamous epithelium with trichilemmal keratinization without granular layer interposition. Vulvar proliferating trichilemmal cyst is very rare, with, to the best of our knowledge, only 3 cases previously reported in the literature. We describe a 39-year-old woman with recurrent PTT on the left labium majus of the vulva, which had been excised from the same side 5 years before. She had a palpable nodule, approximately 2 cm in size, which was firm, mobile, and nontender; without erythema and ulceration; and covered by normal skin on the vulva. There was no inguinal lymphadenopathy. The lesion was removed by wide surgical excision; because of the tissue elasticity, primary closure was possible. The pathology result was reported as proliferating trichilemmal carcinoma with tumor-free margins. Although local recurrence after wide excision is rare, we recommend complete excision for treatment of PTT and long-term follow-up because of the possibility of recurrence.