Common symptoms of rectal cancer include abdominal pain, changes in stool characteristics, and rectal bleeding. These symptoms could suggest the possibility of rectal cancer. An initial examination can be conducted via a digital rectal exam to preliminarily exclude rectal cancer. If a mass is felt during the digital rectal exam, a high suspicion of rectal cancer should be maintained. Additionally, a colonoscopy can be performed for a definitive diagnosis. If a mass on the rectal mucosa is observed during the colonoscopy, a biopsy can be conducted for histopathological examination to determine the nature of the mass. Generally, if the surface of the mass is uneven, brittle, and bleeds easily, the likelihood of malignancy is high while a smooth surface suggests a greater possibility of benignity.