A 47-year-old man presents to the office with a 1-month history of passing blood in...

Visible rectal bleeding, even in the absence of systemic symptoms, warrants diagnostic colonoscopy to rule out colorectal cancer, polyps, or IBD—especially in adults over 40. FIT is for asymptomatic screening only.

Toronto Notes 2023 – Gastroenterology, “Approach to Lower GI Bleeding”:

“In patients with overt rectal bleeding, colonoscopy is the investigation of choice regardless of age or FIT status.”

MCCQE1 Objectives (Internal Medicine > Gastroenterology > 47-1):

“Candidates must evaluate rectal bleeding with colonoscopy, even in the presence of minor findings on physical exam (e.g., skin tag).”

FIT (A) is not appropriate for symptomatic patients. CEA (D) is a tumor marker for surveillance, not diagnosis. CT colonography (C) is less sensitive for lesions than colonoscopy.