A closed sac (sebaceous gland) within the tissue containing oily or fatty semi-solid material. These cysts are found most commonly on the genitalia, vulva or labia. Features include a nontender, small lump in the skin. Sebaceous cysts which turn red or tender may require treatment with oral antibiotics. Warm wet compresses may help the cyst expel some of its contents. Surgical excision of the cyst may be necessary to prevent recurrence.