Colorectal Cancer

Colorectal cancer, also known as bowel cancer or colon cancer, is any cancer that affects the colon and rectum.

About Colorectal Cancer

Cancer affecting the colon and/or rectum is common, affecting 1 in 21 men and 1 and 23 women in the United States. Screenings have helped patients get treatment from a gastrointestinal cancer specialist early, leading to a decrease in death rate.

Most colorectal cancers start as a growth, called a polyp, on the inner lining of the colon or rectum. While not all polyps progress to cancer, some can change into cancer over time, usually over the course of many years. Polyps may be small and produce few if any, symptoms. For this reason, doctors recommend regular screening tests to help prevent colon cancer by identifying and removing polyps before they turn into cancer. There are various factors that can increase the risk of a polyp developing into cancer, such as a polyp larger than one centimeter, more than three polyps found, or if dysplasia(the presence of abnormal cells)is seen in a polyp after removal.

The different types of polyps include:

• Adenomatous polyps (adenomas) sometimes change into cancer. Because of this, adenomas are called a pre-cancerous condition. The 3 types of adenomas are tubular, villous, and tubulovillous.
• Hyperplastic polyps and inflammatory polyps are more common, but in general they are not pre-cancerous. Some people with large (more than 1cm) hyperplastic polyps might need colorectal cancer screening with colonoscopy more often to monitor the polyp.
• Sessile serrated polyps (SSP) and traditional serrated adenomas (TSA) are often treated like adenomas because they have a higher risk of colorectal cancer.

Types of Colorectal Cancer

Most colorectal cancers are adenocarcinomas, which means the cancer starts in the cells that produce the mucus that lubricates the inside of the colon and rectum.

Other, less common types of tumors that can also start in the colon and rectum:

• Carcinoid tumors grow from special hormone-making cells in the intestine
• Gastrointestinal stromal tumors (GISTs) grow from special cells in the wall of the colon called the interstitial cells of Cajal. Some are benign. These tumors can be found anywhere in the digestive tract but are not common in the colon
• Lymphomas are cancers of immune system cells. They mostly start in lymph nodes, but they can also start in the colon, rectum, or other organs. Information on lymphomas of the digestive system can be found in non-Hodgkin lymphoma
• Sarcomas can start in blood vessels, muscle layers, or other connective tissues in the wall of the colon and rectum. Sarcomas of the colon or rectum are rare

Symptoms of Colorectal Cancer:

• A change in bowel habits
• A feeling that the bowel does not empty properly after a bowel movement
• A feeling of fullness in the abdomen, even after not eating for a while
• A lump in the abdomen or the back passage felt by your doctor
• Diarrhea or constipation
• Blood in feces that makes stool look black
• Bright red blood coming from the rectum
• Pain and bloating in the abdomen
• Fatigue or tiredness
• Unexplained weight loss
• Unexplained iron deficiency in men or in women after menopause

Risk Factors for Colorectal Cancer

Researchers have found several factors that can increase a person’s risk of colorectal cancer, but it’s not yet clear what exactly causes the cancer.

Other risk factors for colorectal cancer include:

• Age: Colorectal cancer typically affects those over the age of 50, though it can occur at any age
• Comorbid conditions: Type 2 diabetes, inflammatory bowel disease, and obesity are associated with colorectal cancer
• Family history: Inherited genetic mutation, such as Lynch syndrome (hereditary non-polyposis colorectal cancer, or HNPCC) and familial adenomatous polyposis (FAP), can increase one's risk of colorectal cancer. African Americans and Jews of Eastern European descent (Ashkenazi Jews) are at higher risk for developing colorectal cancer than other races.
• Health history: Individuals with a history of colorectal polyps or colorectal cancer may increase one's risk for later disease
• Personal history: Colorectal cancer is associated with lack of physical activity, poor diet, smoking, and moderate-to-heavy alcohol consumption

Treating Colorectal Cancer

Treatment requires accurate diagnosis and a care plan tailored to the specific type of tumor, the tumor’s location, and the overall needs of the patient. The different behavior of different tumor types helps drive decisions about treatment, which may include combinations of surgery, radiation therapy, and chemotherapy.

Care Team Approach

Patients are cared for by a dedicated multidisciplinary care team, meaning you will benefit from the expertise of multiple specialists across a variety of disciplines. Our board-certified and fellowship-trained gastroenterologists have extensive experience treating disorders of the liver and digestive system and work alongside a team of digestive health experts, including surgical and other disease specialists, physician assistants, nurses, advanced practice providers, dietitians, social workers, and more, providing unparalleled care for patients every step of the way.

As faculty physicians of the Dell Medical School at The University of Texas at Austin, we are able to leverage collaboration throughout The University of Texas system. We collaborate with our colleagues to utilize the latest research, diagnostic, and treatment techniques, allowing us to offer treatment plans specific to your needs.

Learn More About Your Care Team