[Giant keratoacanthoma in an immunocompetent patient with detection of HPV 11]

A 47-year-old immunocompetent man presented with a nodule on the right side of the upper lip that appeared suddenly and grew rapidly. Histological examination was consistent with the diagnosis of keratoacanthoma which is often associated with immunosuppression. Low-risk HPV type 11 was detected in the PCR analysis. While formerly one often waited for spontaneous regression of keratoacanthomas, today one routinely treats them as a well-differentiated squamous cell carcinoma. Complete surgical excision was not possible in our patient because of the size of the tumor. Radiation with a cumulative dose of 30 Gray (15 sessions of 2 Gray) led to complete remission. In addition to ultraviolet exposure, trauma, genetic factors and chemical carcinogens, HPV should be considered as a possible cofactor in the etiology of keratoacanthoma.