Squamous cell carcinoma (SCC). Light micrograph (LM) of a SCC in the vulva of a cancer patient. Vulvar cancer is a cancer of the vulva, the outer portion of the female genitals. It most commonly affects the outer vaginal lips. Less often, the inner vaginal lips, clitoris, or vaginal glands. Symptoms include a lump, itchiness, changes in the skin, or bleeding from the vulva. Human papillomavirus (HPV) is responsible for about 60% of squamous cell carcinomas of the vulva, and is the most common cause of vulval cancer in young women. SCC is the second most common form of skin cancer and arises from the uncontrolled proliferation of squamous cells, flattened cells in the skin and mucous membranes. Standard treatments may include surgery, radiation therapy, chemotherapy, and biologic therapy. Magnification: x 150 when printed at 10 centimetres high.