Er:YAG laser followed by topical podophyllotoxin for hard‐to‐treat palmoplantar warts

BACKGROUND AND OBJECTIVES: Palmoplantar warts are often hard to treat. They tend to relapse and the course of therapy is frustrating in many cases. The erbium:YAG laser(Er:YAG) with a wavelength of 2.94 rm is capable of achieving a rapid and precise ablation of warts, but about 14% of patients are non-responders as shown in a previous study. Podophyllotoxin is an established antimitotic agent derived from podophyllum plant resin, approved for human papilloma virus (HPV)-induced genital warts. The combination of both ablative Er:YAG laser and topical 0.5% podophyllotoxin solution in hard-to-treat palmoplantar HPV warts was investigated. PATIENTS AND METHODS: Thirty-five patients with hard-to-treat warts(palmar or plantar) with a mean age of (32.2+12.1) years, range 17-50 years, with various pretreatments that had failed, were treated once by Er:YAG laser ablation with a spot size of 3 mm, a frequency between 8 Hz and 10 Hz, and a fluence of 5.7-11.3 J/cm2. After wound healing, topical podophyllotoxin 0.5% solution was applied for 3 days followed by a break of 4 days. Four to six treatment cycles with podophyllotoxin were performed. RESULTS: After laser treatment followed by topical podophyllotoxin cream a complete response was observed in 31 patients (88.6%). Two patients with plantar warts and a complete response showed a relapse within 3 months after treatment (5.7%). None of the patients developed pigmentary changes,wound infections or scarring. CONCLUSION: The therapy of hard-to-treat warts with a combination of Er:YAG laser and topical podophyllotoxin is safe and effective. Compared with laser alone, the CR percentage seems to be higher and the percentage of relapses reduced.