A Two-week Interval Is Better Than a Three-week Interval for Reducing the Recurrence Rate of Hand-foot Viral Warts after Cryotherapy: A Retrospective Review of 560 Hand-foot Viral Warts Patients.

BACKGROUND Viral warts are a common infectious disease and liquid nitrogen cryotherapy is one of the most common methods for treatment of these warts. Hand-foot viral warts frequently recur and reduce quality of life as well. OBJECTIVE To find the ideal treatment interval between cryotherapy sessions that can influence not only the cure rate but also the recurrence rate for hand-foot viral warts. METHODS A retrospective study was designed to compare a 2 week interval and a 3 week interval between cryotherapy sessions on hand-foot viral warts with respect to cure rate, recurrence rate, treatment number, duration of treatment, mean time to recurrence and adverse events. RESULTS A total of 560 patients were enrolled. The overall cure rate was 75.7% and the recurrence rate was 19.6%. The mean time to recurrence was 7.8 months (range 1~26 months). For the 2-week and 3-week groups, cure rates were, respectively, 76.6% (196) and 75.0% (228); recurrence rates were 13.3% (26) and 25.0% (57). The mean time to recurrence was 9.8 months and 6.9 months, respectively. Adverse events were not statistically different. CONCLUSION We suggested that 2-week cryotherapy is optimal not only because of the rapid cure but also because of the lower recurrence rate and similar adverse events.