6. Narrow Stools
Stools that appear thinner or narrower than usual can be a sign of colon cancer, especially if the change is persistent. This occurs when a growing tumor narrows the inside of the colon, restricting the passage of stool.
While narrow stools alone are not diagnostic, they become more concerning when accompanied by other symptoms such as blood in the stool or abdominal pain. Persistent changes in stool shape should prompt evaluation with colonoscopy to exclude malignancy or other obstructive lesions.
7. Feeling of Incomplete Evacuation
A sensation of incomplete bowel emptying, known medically as tenesmus, may indicate irritation or obstruction in the lower colon or rectum caused by a tumor. This feeling can cause frequent urges to have a bowel movement without relief.
Tenesmus often accompanies other symptoms such as pain and bleeding, and its persistence should never be dismissed. A thorough clinical examination and possibly endoscopic evaluation are necessary to determine the cause.
8. Unexplained Anemia
Iron deficiency anemia without an obvious cause is a significant early sign of colon cancer, particularly in adults over 50. Chronic slow bleeding from the tumor depletes iron stores, leading to anemia characterized by fatigue, pallor, and shortness of breath.
Routine blood tests revealing low hemoglobin and iron levels should prompt investigation for gastrointestinal blood loss, including a colonoscopy. Anemia may be the first clue to a hidden colorectal tumor before other symptoms appear.
