Demonstration of HPV 24 in long-standing Heck's disease with malignant transformation.

We report on the rare case of a 64-year-old European woman with a viral acanthoma of the oral mucosa of the clinical Heck type with unprecedented molecular-biological proof of HPV 24 DNA and so far undescribed malignant transformation with a long existence of the vegetation. After surgical therapy a circumscribed relapse of viral acanthoma developed, which responded favourably to a combined antiviral and antiproliferative therapy with acitretin perorally and interferon, first subcutaneously, later intralesionally for 3 months.