Rectal bleeding and other gastrointestinal symptoms often cause concern. This concern arises from symptom overlap between benign conditions like hemorrhoids and serious diseases such as colon cancer. This article clarifies the relationship between hemorrhoids and colon cancer, distinguishing between these two conditions.
Understanding Hemorrhoids
Hemorrhoids are swollen veins located in the rectum or around the anus. They are categorized into two main types: internal hemorrhoids, which develop inside the rectum, and external hemorrhoids, which form under the skin around the anus. Internal hemorrhoids usually don’t cause pain unless they prolapse. External hemorrhoids can be itchy, painful, and appear as a tender lump.
Common symptoms include painless, bright red bleeding during bowel movements. Other symptoms include itching, irritation, discomfort, or swelling in the anal area. They often develop from increased pressure in the lower rectum due to straining, chronic constipation or diarrhea, prolonged sitting, or pregnancy. About 50% of adults experience hemorrhoid symptoms by age 50.
Understanding Colon Cancer
Colon cancer begins in the large intestine. It develops from small, non-cancerous growths called polyps on the colon’s inner lining. While most polyps are harmless, some can become cancerous over time. If undetected, it can spread through the colon wall and to other body parts.
Symptoms vary and may not be present in early stages. When symptoms appear, they often include changes in bowel habits like new diarrhea or constipation, or altered stool consistency or narrowness. Rectal bleeding or blood in the stool is common, appearing as darker blood mixed with stool or bright red blood if the tumor is low. Other signs include persistent abdominal discomfort (cramps, gas, pain), a feeling of incomplete bowel emptying, unexplained weight loss, and fatigue.
Overlapping Symptoms and Key Distinctions
Rectal bleeding is a significant overlapping symptom. With hemorrhoids, bleeding is bright red and usually occurs during or after a bowel movement. In contrast, colon cancer-related bleeding can be bright or dark red, may be mixed with stool, or appear black and tarry if from higher in the digestive tract. Bleeding from colon cancer can also occur at any time, not just during bowel movements.
Changes in bowel habits can also occur with both conditions. However, prolonged, unexplained changes or a feeling of incomplete bowel emptying are more indicative of colon cancer. Symptoms more specific to colon cancer include unexplained weight loss, persistent abdominal pain or cramping, significant fatigue, and unusually narrow stools.
The Likelihood of Co-occurrence
Hemorrhoids and colon cancer are distinct conditions. Having hemorrhoids does not increase colon cancer risk, nor does colon cancer cause hemorrhoids. They are separate conditions that share some similar symptoms.
Colon cancer originates from polyps, which are not related to hemorrhoids. Because symptoms like rectal bleeding and changes in bowel habits can overlap, do not assume symptoms are solely due to hemorrhoids. A medical evaluation is necessary to determine the cause of symptoms.
When to Seek Medical Evaluation
Any new or persistent rectal bleeding, changes in bowel habits, or other concerning gastrointestinal symptoms warrant a medical evaluation. Consult a doctor, as self-diagnosis is insufficient to distinguish between hemorrhoids and more serious conditions like colon cancer. A healthcare provider can conduct a thorough examination, including a physical exam, digital rectal exam, or stool tests.
For a definitive diagnosis, a colonoscopy may be recommended, especially with visible rectal bleeding without clear hemorrhoid evidence, or other concerning symptoms. Regular colon cancer screening, such as colonoscopy or stool-based tests, is recommended for individuals starting around age 45 or 50, or earlier if risk factors exist. These screenings are important for detecting polyps before they become cancerous or for identifying cancer at an early, more treatable stage.