Fig. 1
From: Synchronous anal canal carcinoma in a heterosexual couple
The biopsy of the anal lesion of the female revealed a well-differentiated squamous cell carcinoma (a), and the male had a poorly differentiated squamous cell carcinoma (b) with a prominent lymphoid infiltrate (*), hematoxylin and eosin staining. Both lesions (c, d) demonstrate strong and diffuse p16 immunoreactivity (brown) and there is no p16 expression in the adjacent rectal glands (*). Magnification X 200