The colon is the last section of the digestive system, also known as the large intestine. Colon cancer begins in the colon and can spread to other parts of the body. This cancer often develops in small clumps of cells known as polyps. Symptoms typically don’t show themselves until the polyps change into cancerous cells. Although colon cancer is typically diagnosed in older patients, it may also occur in younger patients as well.

Read on for the most prominent signs of colon cancer:

1. Diarrhea or constipation

Changes to your bowel movements are always a cause for concern. A doctor should be consulted immediately if you suffer any long-term irregularities in bowel movements. Both diarrhea and constipation can be symptoms of colon cancer, so it is important to see a doctor if these persist. It is especially concerning if you have diarrhea or constipation accompanied by any of the other symptoms listed below.

2. Rectal bleeding

The development of polyps and cancerous cells in the colon can cause ruptures and tears that may result in bloody stools. This bleeding can be subtle, but any abnormal bleeding should be brought to the attention of a doctor immediately.

3. Blood in your stool

Obvious signs of bleeding may not present themselves. That’s why you should keep an eye on your stool if you suspect colon cancer. Blood may appear subtly in stool, and you may notice the blood on your toilet paper as well. Bleeding and blood in the stool can be caused by a number of other conditions, including hemorrhoids, anal fissures, IBD, and ulcers. Always consult a physician if you are having rectal bleeding or finding blood in the stool.

4. Abdominal pain

Abdominal pain and cramps is one of the most obvious signs of colon cancer. Pain in this area is hard to ignore, and it could even become unbearable. Pain that begins suddenly, is long-lasting, and is extremely painful should be immediate cause for concern. The pain is caused by the effect cancer is having on your colon and entire abdomen. Polyps and colon cancer can also cause bloating and cramping.

5. Feeling like the bowel won’t empty

While similar to constipation, this is quite a different symptom. Rather than feeling like you need a bowel movement but can’t, this is a feeling of constantly needing to relieve yourself. This is typically a late-stage sign of colon cancer and is cause for immediate concern. It can be difficult to differentiate this symptom from constipation, but it shouldn’t take you long to notice differences.