Rectal mucosa shows an invasive carcinoma formed of irregular glandular formations lined by several layers of columnar malignant cells with related desmoplastic exhibiting moderate anaplasia and mitosis. Stroma is fibrotic. Rest of fragments show an adenomatous polyp formed of tubular and villous glands lined by columnar cells with reduced mucigenic activity and moderate dysplasia with focal infiltrating glands. There is detected invasive groups within desmoplastic stroma. Picture is consistent with adenocarcinoma arising on top of tubulovillous adenomatous polyp.
Large rectal mass.
Soft tissue fragments collectively measured 1 cm, totally embedded.
Rectal mass, endoscopic biopsy: