Sebaceous or inclusion cysts are caused by inflammatoryblockage of the sebaceous gland ducts and are small, smooth, nodular masses, usually arising from the inner sur-faces of the labia minora and majora, that contain cheesy, sebaceous material. They may be easily excised if their size or position is troublesome.
The round ligament inserts into the labium majus, car-rying an investment of peritoneum. On occasion, peritoneal fluid may accumulate therein, causing a cyst of the canalof Nuck or hydrocele. If such cysts reach symptomaticsize, excision is usually required.
Fibromas (fibromyomas) arise from the connectivetissue and smooth muscle elements of vulva and vagina and are usually small and asymptomatic. Sarcomatous change is extremely uncommon, although edema and degenerative changes may make such lesions suspicious for malignancy. Treatment is surgical excision when the lesions are symp-tomatic or with concerns about malignancy. Lipomas appear much like fibromas, are rare, and are also treated by excision if symptomatic.
Hidradenoma is a rare lesion arising from the sweatglands of the vulva. It is almost always benign, is usually found on the inner surface of the labia majora, and is treated with excision.
Nevi are benign, usually asymptomatic, pigmentedlesions whose importance is that they must be distinguished from malignant melanoma, 3% to 4% of which occur on the external genitalia in females. Biopsy of pigmented vulvar lesions may be warranted, depending on clinical suspicion.