Colonoscopy

Excerpt

In the United States, colorectal cancer represents the third most frequently diagnosed malignancy and the second leading cause of cancer-related mortality. Colonoscopy is recognized as the gold standard modality for colorectal cancer screening and diagnosis, and it also serves as a therapeutic intervention through polypectomy of lesions with malignant potential. This procedure facilitates the diagnosis of numerous nonmalignant colorectal conditions, including ulcerative colitis, diverticular disease, and lower gastrointestinal hemorrhage. Colonoscopy uses a flexible, hand-held endoscope equipped with a high-definition camera positioned at the instrument tip, accompanied by accessory channels enabling insufflation, irrigation, suction, and insertion of additional equipment.

Visual data transmitted from the camera to the display monitor facilitates detection of colorectal mucosal abnormalities and enables appropriate interventions, including tissue biopsy, polypectomy, stricture dilatation, and hemostasis of bleeding lesions. Colonoscopy demonstrates superior diagnostic sensitivity and specificity compared to alternative modalities such as barium enema, fecal occult blood testing, and computed tomography colonography. Therefore, despite the substantial learning curve required for technical proficiency, colonoscopy remains widely accepted as the gold standard for screening and diagnosing various colorectal pathologies, particularly malignancies.