The presenting symptoms were bright red blood from the rectum (83%), rectal pain (33%), change in bowel habits (28%), rectal mass (22%), nonbloody rectal discharge (11%),
[ascopost.com]
Other rectal mass lesions show hypointense signal on T1-weighted imaging.
[ncbi.nlm.nih.gov]
Most patients (89%) had an incorrect initial diagnosis, including hemorrhoids (44%), rectal polyp or benign mass (22%), nonmelanotic malignant neoplasms (17%), and adenocarcinoma
[ascopost.com]