Whatever procedure is used, patients are at substantial risk of recurrence, particularly when the lesions are high grade or multifocal. The most common sites of recurrence are the perianal skin, presacral area, and clitoral hood. About 4% of patients treated for VIN subsequently develop invasive cancer.[8,9]
Because of the physical and psychosexual morbidity associated with many vulvar surgical procedures, nonsurgical approaches have been studied. Some of these approaches, including topical 5-fluorouracil, gamma-interferon, bleomycin, and trinitrochlorobenzene, have been largely abandoned because of intolerable local side effects, such as pain, irritation, and ulceration, or high recurrence rates.[10,11] Photodynamic therapy, using topically applied 5-aminolevulinic acid as the sensitizing agent for 635 nm laser light, has also been studied. However, data are limited to small case series with variable response rates.[12,13][Level of evidence: 3iiiDiv]
More recently, among women with high-grade VIN, substantial response rates and acceptable tolerability were reported for topical imiquimod 5%, an immune-response modifier with activity in HPV 6/11-associated vulvar condylomata. Three randomized placebo-controlled trials (including a total of 104 patients) with clinical response as their primary endpoints.[Level of evidence: 1iDiv] have been reported in either peer-reviewed-journal or abstract format.[14,15,16,17] The results of these trials were summarized in a systematic review. At 5 to 6 months, the complete and partial response rates in patients were 36 of 62 and 18 of 62 in the combined imiquimod arms versus 0 of 42 and 1 of 42 in the combined placebo arms (relative risk [RR], 11.95; 95% confidence interval [CI], 3.21–44.51).
In the only trial reporting progression to cancer (at 12 months), there was no difference in progression rate, but the trial was severely underpowered because only 3 of the total 52 women included developed invasive disease by 12 months. The only trial reporting quality of life  showed no difference between imiquimod and placebo. Local side effects of imiquimod included pain, edema, erythema, and a single case of erosion. However, no patients had to discontinue treatment as a result of toxicity.
Standard treatment options:
- Separate excision of focal lesions.
- Wide local excision.
- CO2 laser surgery and vaporization.[2,6] A disadvantage of vaporization is that it does not provide tissue for histologic examination to confirm complete removal of the lesion and the absence of invasive disease.
- Ultrasonic surgical aspiration (USA).[2,6]
- Superficial skinning vulvectomy with or without grafting.
- Topical imiquimod for patients wishing to avoid surgery.[11,14,15,16,17]
Current Clinical Trials
Check for U.S. clinical trials from NCI's list of cancer clinical trials that are now accepting patients with stage 0 vulvar cancer. The list of clinical trials can be further narrowed by location, drug, intervention, and other criteria.