Colon cancer develops from growths, or polyps, in the colon’s inner lining. It is important to catch precancerous polyps and have them removed—if left untreated, the cancer may spread throughout the body. Catching it early on also makes treatments like the colon cancer clinical trials with MD Anderson, medications like Opdivo, and the Vectibix immunotherapy treatment much more effective. It’s valuable to be aware of these early symptoms of colon cancer:

1. Blood in stool
While blood in stool may not always be colon cancer, it is certainly a reason for concern. If you notice blood in your stool, after wiping, or your stool is a dark or bright red, it is important that you check in with your healthcare provider.

2. Changes in bowel movements and habits
If you have chronic diarrhea or constipation, or you feel as though your bowels are still full after using the restroom, you should speak to your healthcare provider. Any abnormal changes in your bowel movements or habits should not go unnoticed or unreported.

3. Abdominal pain
Many things can cause abdominal pain; however, it is an early symptom of colon cancer. With polyps, constipation, or bloating (all are results of colon cancer), it is likely that you will experience abdominal pain. Particularly if you experience bowel blockages that inhibit the passage of liquid, gas, or solid waste, your abdomen may cramp uncomfortably.

4. Bloating
Colon cancer disturbs the gastrointestinal (GI) tract which is what causes the changes in bowel habits as well as other digestive issues. When you experience these issues, bloating can occur and contribute to further abdominal pain. If your bloat lasts longer than a week or is paired with other symptoms, you should check in with your healthcare provider.

5. Vomiting
Bowel obstruction as a result of colon cancer can turn to nausea and vomiting, and this can also be a result of constipation. If you can’t tolerate fluids or have been vomiting for over 24 hours, you should seek medical attention immediately.

6. Unexplained weight loss
If you’re not trying to lose weight and you’ve noticed a drop in your body weight, you should speak to your healthcare provider. Unexplained weight loss can be a result of many different things, but no matter the cause, it should always be checked out.