When you have colon cancer, your body undergoes a series of changes due to the growth and potential spread of the cancerous cells. Here's a step-by-step explanation of what happens: 1. Formation of Tumors: Colon cancer often begins as small growths called polyps in the lining of the colon or rectum. Over time, these polyps can become cancerous and start to grow, forming tumors. 2. Local Invasion: As the tumor grows, it can invade the layers of the colon or rectum wall, causing symptoms such as changes in bowel habits, blood in the stool, or abdominal pain. 3. Lymph Node Involvement: The next stage often involves the cancer spreading to nearby lymph nodes. Lymph nodes are part of the immune system and are located throughout the body, including near the colon. 4. Distant Metastasis: If the cancer is not treated, it can spread to other parts of the body. The most common site for distant spread from colon cancer is the liver, although it can also spread to the lungs, bones, and other organs. 5. Systemic Effects: As the cancer spreads, it can cause a range of systemic effects, including weight loss, fatigue, and anemia. It can also lead to a condition called cachexia, which is a severe wasting syndrome associated with cancer. 6. Treatment Complications: Depending on the treatment, there may be additional effects on the body, such as surgical complications, side effects from chemotherapy or radiation, and the potential for bowel changes if surgery involves the removal of part of the colon. read more >>

These extra cells grow together and form masses, called tumors. In colorectal cancer, these growths usually start as polyps in the large intestine (colon or rectum). ... Colorectal cancer spreads first to nearby lymph nodes. From there it may spread to other parts of the body, usually the liver.read more >>