What is the most common type of primary anal cancer?
~80% of anal cancers are squamous cell carcinomas. The other less common histological types are adenocarcinoma, basal cell carcinoma, and melanoma.
Large slightly T2 hyperintense tumour involving the whole length of the anus, with a 5 cm extension proximal to the puborectalis. There is invasion of the levator and puborectalis muscles. The lesion is abutting the posterior aspect of the prostate but no evidence of invasion of the prostate, urethra, bladder or seminal vesicles. There is no evidence of abnormal lymph nodes in the perirectal region or bilateral groins.
Diffusely decreased T2 intensity is identified in the imaged skeleton, including the sacrum, pelvis and bilateral femoral heads. No cortical destruction is noted.