A study into the use of microwaves in the treatment of plantar warts and verrucae

Introduction: The human papilloma virus (HPV) infects keratinocytes of the skin and mucous membranes, and is associated with the induction of cutaneous warts. Cutaneous warts are a common problem in clinic. Therapies, including cryotherapy, laser, and radiofrequency devices show low efficacy and induce discomfort through tissue destruction. Outcomes from these therapies have been shown by meta-analyses to have limited benefit. Microwaves are readily capable of passing through highly keratinised skin to deliver energy and induce heating of the tissue in a highly controllable, uniform manner. The object of this study was to determine the effects of microwave on cutaneous HPV infection. Patients and methods: We undertook a pilot study of microwave therapy to the skin in 32 consecutive adults with 52 recalcitrant, long-lived viral cutaneous plantar warts. For each patient, the largest wart was selected for treatment. Following assessment and consent, subjects received up to four treatments using microwave energy (of between 5-10W up to a maximum of 5 seconds). No local analgesia was used. Treatments occurred approximately 3-4 weeks apart and subjects were subsequently reviewed at a later appointment to assess if resolution had occurred. Resolution was declared if the wart was no longer visible, the normal dermatoglyphics had been restored and there was no pain on lateral compression of the former lesion. Results: At the conclusion of the study, 41 (75.9 %) of lesions had cleared with 13 (23.9 %) unresolved. Patients reported significant reduction in their wart pain following treatment. Conclusion: The results from this pilot study compares favourably with previous studies showing a clearance rate of 23-33 % for cryotherapy or salicylic acid.