equate for keratinocyte necrosis, melanocytes may be destroyed at -5°C. Consequently, the potential for post-exposure hypopigmentation
also exists, especially in dark skinned individuals. But perhaps the greatest morbidity is not the immediate burns or pigmentation changes, but, rather, the delay in proper treatment of a malignant lesion masquerading as a viral wart.
In summary, the above case clearly demonstrates a poor outcome
following multiple treatments with an OTC wart-freezing device. But given the lack of prospective data comparing OTC wart-freezing cryotherapy to standard cryotherapy with liquid nitrogen, only tentative conclusions regarding the safety and efficacy
of these OTC products should be made.
The authors have no conflict of interest to declare.
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