Carbon dioxide (CO2)-laser therapy cures macroscopic lesions, but viral genome is not eradicated in men with therapy-resistant HPV infection.

Background and Objectives: We have evaluated the efficacy of CO2-laser in eradicating human papillomavirus (HPV) DNA from genitoanal skin lesions.
Study Design: Biopsies of 38 male patients with histologically confirmed HPV-infection after an average of 2 years of follow-up were analyzed. Post-treatment biopsies were obtained from all residual or recurrent HPV-suspect (acetowhite) lesions in 23 patients.
Results: After an average of three separate CO2-laser treatments, 15 of 38 patients were devoid of any clinical or acetowhite lesions. By in situ hybridization (ISH), the frequency of HPV-types 6/11 decreased from 52% to 26%, and HPV-types 16/18 decreased from 48% to 17%, respectively, in 23 patients biopsied twice. When ISH-negative biopsies were further analyzed with polymerase chain reaction (PCR) and southern blotting (SB) for HPV-16, HPV-types 16/18 were detected in a total of 65% of biopsies before CO2-laser therapy, and in 61% after the therapy. The cure rate achieved with CO2-laser was 39% (15/38) according to clinical, 61% (14/23) according to histopathological, and 26% (6/23) according to molecular biological criteria. The frequency of Bowenoid papulosis was reduced from 57% (13/23) to 17% (4/23).
Conclusions: Although CO2-laser is ineffective in eradicating HPV genome from therapy-resistant penile warts, the treatment reduces the recurrence of atypical changes and visible warts.