Spontaneous regression of genital warts can occur in up to 30% of affected patients. Regression, however, does not necessarily lead to viral clearance, as viral genomes can be detected in normal epithelium for months to years following clearing of visible disease. In immunocompetent women, however, the cell-mediated immunity that resulted in lesion regression most likely controls latent HPV infection. Disease recurrence is, therefore, less likely. Immunosuppression, on the other hand, does not confer the same protection. Women at increased risk of developing HPV-related manifestations thus include those receiving long-term corticosteroid therapy or chronic immunosuppressive treatment, as well as immunosuppressed women with HIV infection. Antiviral chemotherapies are particularly critical for these populations, if disease recurrences are to be minimized (Stanley, 2003).

The majority of currently available treatment options for genital warts, however, are not targeted antiviral therapies. The goal in general has been physical destruction or removal of visible disease, not eradication of HPV infection, as evidenced by the currently recommended treatment regimens for external genital warts. These include podofilox 0.5% solution or gel (patient-applied) as well as the provider-administered therapies: cryotherapy, podophyllin resin 10%-25%, trichloroacetic or bichloroacetic acid 80%-90%, surgical removal and laser therapy (CDC, 2006; see Table). Such therapies have been the mainstay of treatment. While most are equivalent in terms of clearance rates, recurrence rates can be high, particularly for laser therapy and trichloroacetic acid, where the rate exceeds 60% (Maw, 2004). Local irritation (e.g., pain, burning and soreness), erythema, edema and, at times, ulceration can result from the use of any of the medications. Careless or excessive use can result in extensive burning of the epithelium, with resultant scar formation. Surgical excision or laser vaporization should be reserved for patients with extensive disease.

The antiviral treatments podofilox and imiquimod are newer therapeutic choices that both patients and providers find both efficacious and preferable. Clearance rates for the two treatments are similar and compare favorably to any of the treatments listed above. The added benefit of imiquimod, as demonstrated in numerous studies, has been its significantly lower recurrence rates (9-19%). Intralesional interferon, a medication with antiproliferative, antiviral and immunomodulatory properties, has, unlike imiquimod, demonstrated limited efficacy, and is not recommended for first line therapy in treating either warts or VIN (Stanley, 2003). Its use, however, can be considered an alternative regimen for the treatment of external genital warts, bearing in mind the need for repetitive office visits, inconvenient route of administration and its association with a high frequency of systemic adverse events (CDC, 2006). Finally, several medications should not be used in the treatment of genital warts and bear mention. Cidofovir, 5-fluorouracil, and isotretinoin are not recommended for use in the treatment of warts, as clearance rates have been unacceptably low (Maw, 2004).

Treatment Options and Recurrence Rates: External Genital Warts