Sometimes I sit and feel sad about the chair. This site is about Total Mesorectal Excision, a surgical approach to rectal cancer.
Here’s a great example of a low rectal cancer, very close to the top of the anal canal. It has irregular outer margins and (not shown on this image), it also has small peri-rectal lymph nodes.
In my country, Canada, this might receive neoadjuvant chemotherapy, then surgery. The surgery might be “AP resection”. Lastly after healing from surgery, would be radiotherapy.
This particular patient has no liver metastases, and no pelvic sidewall or paraaortic lymphadenopathy.
Here’s a different example, of a low rectal tumor definitely involving part of the top of the anal canal.