Despite the adoption of rectal MRI as a mandatory staging tool for rectal cancer, inconsistencies still exist in defining anatomic landmarks even among experts (Lambregts DMJ et al. 2022).

This exhibit aims to review controversies in anatomic issues, propose the best opinion based on the evolving literature, and discuss impact on management.Anatomic landmarks to be discussed include:Re-definition of the rectum and its upper/lower boundaries.-The anatomy of the anal sphincter and staging of tumors involving this structure.-The definition of circumferential resection margin (CRM) will vary depending on surgical procedure and does not equate to mesorectal fascia (MRF). -Clarify the difference between peritoneal involvement and mesorectal fascia involvement in the upper rectum.-Clarify the anatomic boundaries of lateral pelvic nodes and their clinical significance.