One possible reason for the high numbers of deaths from colorectal cancer (a preventable form of cancer) is that those at risk are not being screened, or not receiving appropriate screening. Screening tests can be unpleasant, but there are new tests on the horizon that may help with screening compliance.
DNA test. One emerging test uses DNA to detect abnormal cells in a stool sample. Some studies have shown these tests to be quite accurate in predicting the presence of colon and rectal cancers.
Virtual colonoscopy. Virtual colonoscopy, also called computerized tomography (CT) colonography, uses a CT scan to take images of the abdomen. This test requires a clean colon, much like a conventional colonoscopy. It's not yet known if this new test is as sensitive at detecting colorectal cancer as a colonoscopy.
Wireless capsule endoscopy. This test, which has gotten much media attention, beings with the patient swallowing a tiny camera. The patient wears a recorder around the waist, which receives the photos from the camera as it passes through the digestive tract. The camera passes out of the body naturally.
However, until these tests are perfected and guidelines for their most effective use are determined, colonoscopy is still the best way to detect colorectal cancer and diagnose other digestive diseases.
Ahlquist DA, Zou H, Domanico M, et al. "Next-generation stool DNA test accurately detects colorectal cancer and large adenomas." Gastroenterology 2012 Feb;142:248-256; quiz e25-e26. 22 Jan 2013.