Nearly 150,000 new cases of colorectal (colon and rectal) cancer are discovered each year, according to the National Cancer Institute. Of those, 50,000 people will die of the disease. The U.S. Centers for Disease Control and Prevention (CDC) lists colorectal cancer as the second leading cancer killer in the U.S., a high number considering that treatment is 95 percent effective if caught in the earliest stages. Unfortunately, few people with colon cancer have early warning signs of the disease.
How it Begins
Colorectal cancer begins as small polyps, what the Mayo Clinic calls "clumps of precancerous cells," in the lining of the colon (part of the large intestine). If left untreated, these polyps enlarge and expand in number to the point of interfering with normal body functions. Polyps are also susceptible to the abnormal cell development that leads to cancer. Left undetected, they can develop into colorectal cancer.
Bowel Habits
The stools of people with advanced colorectal cancer are bloody, showing as bright red or deep dark burgundy colors, according to the Colorectal Cancer Screening Initiative Foundation (CCSIF). The stools are usually narrow, as well, shaped by the cancerous growths that interfere with normal bowel movements. In later stages of the disease, alternating and unexplained diarrhea and constipation may be experienced. The Mayo Clinic warns that frequent and unexplained bowel changes are a typical symptom of colon cancer, and that these conditions require an immediate medical examination.
Gastrointestinal Problems
People with advanced colon cancer also experience high levels of stomach gas, according to the CCSIF. The discomfort is frequent and persistent, and often accompanied by cramping and bloating, with cramps sometimes lasting for days at a time.
Other Symptoms
People with colon cancer will feel constant fatigue and lack the energy to do even minor activities. Colon cancer sufferers also typically suffer dramatic weight loss over the course of the disease.
