Investigation of choice for diagnosis of CA colon
Colonoscopy
Double contrast barium enema
Triple phase CT
Viual colonoscopy
Colonoscopy is the "gold standard" for establishing the diagnosis of colon cancer. It permits biopsy of a tumour to verify the diagnosis while allowing inspection of the entire colon to exclude metachronous polyps or cancers; the incidence of a synchronous cancer is approximately 3%. Colonoscopy is generally performed even after a cancer is detected by barium enema to obtain a biopsy specimen and to detect (and remove) small polyps that may be missed by the contrast studyRef: Sabiston, 20e, page: 1398
G.I.T