Combination of immunotherapy and photodynamic therapy in the treatment of Bowenoid papulosis

Summary 

Objective

To investigate the feasibility and efficacy of combination of imiquimod and 5-aminolevulinic acid-mediated photodynamic therapy (ALA-PDT) for the treatment of genital Bowenoid papulosis (BP).

Materials and methods

A total of 27 BP patients were randomized into two groups. Fifteen (12 male and 3 female, age 22–56 years old) were treated with topical application of 5% imiquimod cream (three times a week) and ALA-PDT (100J/cm² at 100mW/cm², once a week) for 1–4 times. For comparison, other 12 (6 male and 6 female, age 29–58 years old) were treated with CO₂ laser vaporization as a control. Patients were followed up for 3–12 months. Biopsies were taken from BP lesions prior to treatment and tested for HPV-16 and HPV-18 DNA.

Results

In combined therapy group, 60% (9/15) patients showed complete remission and only one recurred (11.1%) during follow up. Local side effects included mild erythema, edema, erosion and burning and/or stinging sensation. No systemic side effect was found. In CO₂ laser vaporization group, 83.3% (10/12) patients showed complete remission. However, recurrence occurred in six patients (60.0%). Local side effects included mild to moderate edema, erosion, ulceration, delayed healing, prolonged pain and scarring. The difference of recurrence rate between two groups was statistically significant (P<0.05).

Conclusion

Topical application of imiquimod cream and ALA-PDT is safe, effective and associated with low recurrence and less side effect.

Keywords: Bowenoid papulosis, Imiquimod, 5-Aminolevulinic acid, Photodynamic therapy, Combination therapy