Vulvar intraepithelial neoplasia, or VIN, is a precancerous skin condition which affects the vulva. This condition is not cancerous, but vulvar cancer may develop if it is not treated. Many women with VIN experience symptoms such as vulvar pain, but sometimes the disease is asymptomatic. Once the condition has been diagnosed, women with VIN have several treatment options, including surgery and topical chemotherapy.
Vulvar cancer represents around 1% of cancers that affect women only, and approximately 4% of cancers that affect the female reproductive organs. In fact, it is more common for a woman to have an abnormal Pap smear than it is for her to be diagnosed with a vulvar condition. Vulvar intraepithelial neoplasia is a less common issue than cervical cell abnormalities, but it is possible for vulvar lesions to become cancerous if left untreated. It is therefore just as important that vulvar conditions be diagnosed and treated promptly.
The cause of vulvar intraepithelial neoplasia is not well understood, but a number of risk factors have been determined. The presence of one or more risk factors can increase the risk of VIN developing. One of the main risk factors is the presence of human papilloma virus, in particular types 16 and 18. Herpes simplex type 2, which causes genital herpes, also increase the risk of vulvar intraepithelial neoplasia developing. In addition, smoking and reduced immune system function also increases the risks.
Common symptoms of vulvar intraepithelial neoplasia include vulvar pain and itching, or a feeling of burning or tingling. One or more skin lesions may be present; these are often slightly raised and may take on abnormal coloration such as gray, white, pink, or red. What constitutes “abnormal” depends on the normal color of a woman’s vulva, which tends to differ among individuals. Because symptoms can vary, diagnosis is made on the basis of close inspection of the vulvar region followed by biopsy.
For some women, VIN is entirely asymptomatic. This is problematic because, while most cases of VIN remain benign, a small number of cases eventually proceed to vulvar cancer if left untreated. Approximately 4% of women treated for VIN develop invasive vulvar cancer; while an estimated 8% of women who don’t receive treatment go on to develop vulvar cancer. Doctors recommend that women carry out self-inspection at least every six months, to check for lesions or signs of abnormal coloration.
Women diagnosed with vulvar intraepithelial neoplasia have several options for treatment, the most effective of which are topical chemotherapy, surgical excision, and laser ablation. Chemotherapy is usually performed with an agent called 5-fluorouracil; however, this treatment has painful side effects, including the possibility of severe inflammation of the vulva. Even so, chemotherapy is sometimes chosen, partially because it is less likely to produce scarring than other treatment options.
Another treatment, called laser ablation, causes minimal scarring but can be extremely painful. This option uses laser technology to destroy affected tissue, and is most effective if VIN lesions are in an area where no hair is present. The final treatment option is surgery, which is often preferred because pain and healing time is reduced in comparison to chemotherapy and laser ablation. An additional advantage of surgery is that excised tissue can be biopsied.