Human papillomavirus-related squamous cell carcinoma of the anal canal with papillary features.
Human papillomavirus (HPV) related squamous cell carcinoma (SCC) involving the anal canal is a well-known carcinoma associated with high-risk types of HPV. HPV-related SCC with papillary morphology (papillary SCC) has been described in the oropharynx. We describe, for the first time, a case of anal HPV-related squamous carcinoma with papillary morphology. The tumor arose from the anal mucosa. The biopsies revealed a superficially invasive SCC with prominent papillary features and associated in situ carcinoma. The tumor cells were positive for p16 and were also positive for high-risk types of HPV using chromogenic in situ hybridization. The findings are consistent with a HPV-related SCC of the anal canal with papillary features. This tumor shows histologic features similar to a papillary HPV-related SCC of the oropharynx. Additional studies are needed to characterize these lesions.