Human Papillomavirus Detection in Scrotal Squamous Cell Carcinoma: Case Series from a Population-Based Cancer Registry.

Introduction: Scrotal squamous cell carcinomas (SCCs) are rare malignancies that are not considered to be associated with the human papillomavirus (HPV) by the International Agency for Research on Cancer. However, recent studies have detected HPV in these cancers. We sought to determine the presence of HPV types among scrotal cancer cases identified through population-based cancer registries. Methods: Primary scrotal SCCs diagnosed from 2014 to 2015 were identified, and tissue sections from formalin-fixed, paraffin-embedded tissue blocks were obtained for laboratory testing. A pathology review was performed to confirm morphology. HPV testing was performed using L1 consensus polymerase chain reaction analysis. Immunohistochemistry was used to evaluate p16INK4a (p16) expression. Results: Five cases of scrotal SCC were identified from 1 cancer registry. Age at diagnosis ranged from 34 to 75 years (median, 56 years). Four cases were non-Hispanic White, and 1 was non-Hispanic Black. The morphologic subtype of 4 cases was keratinizing (usual), and 1 case was verrucous (warty) histologic subtype. Two of the usual cases of SCC were HPV-negative and p16-negative, and 2 were positive for HPV16 and p16. The verrucous (warty) SCC subtype case was HPV6-positive and p16-negative. Conclusions: The presence of HPV16 and p16 overexpression in the examined tissue specimens lends additional support for the role of HPV in the etiology of scrotal SCC.