Colon and rectal cancer at a glance
- Colon and rectal cancer, together known as colorectal cancer, is caused by the out of control growth of cells in the colon or rectum, both parts of the large intestine that aid in removing body waste.
- According to the National Cancer Institute (NCI), colorectal cancer is the fourth most common cancer in both men and women in the United States.
- Colon and rectal cancers are highly preventable and if diagnosed early, highly treatable.
- Increased use of colonoscopies and tests for blood in stool have decreased the incidence of death in colorectal cancers.
- Treatments for colorectal cancer include surgery to remove the cancer, radiation and chemotherapy.
Colon and rectal cancer
Colon and rectal cancer, known together as colorectal cancer, occurs when normal cells that line the colon or rectum grow out of control becoming cancerous. The rapidly growing cells can cause a mass of tissue, which may or may not be cancerous and may result in a tumor.
Colon cancer forms in the colon located at the lower part of the digestive system. Rectal cancer forms in rectum, which is the last few inches of the large intestine that ends at the anus.
The colon is a 6-foot long muscular tube that connects the rectum to the small intestine. Together, the colon and rectum are called the large intestine. The large intestine processes the body’s waste by removing water from it and storing stool. Once the colon is ready to be emptied, the stool is deposited into the rectum to be eliminated.
According to the American Academy of Family Physicians, 70 to 90 percent of colon and rectal cancers start as polyps, abnormal tissue growths on the inner surface of the colon or rectum.
Most polyps are benign. Small polyps can take up to 10 years to develop into cancer and can be prevented with regular cancer screenings and removal.
The two most common types of polyps found in the colon and rectum are:
- Hyperplastic and inflammatory polyps, which do not typically turn into cancer.
- Adenomatous polyps are pre-cancerous and if left alone, have a high probability of developing into cancer.
As a general rule, the larger the polyp, the greater the chances of it developing into cancer. Oncologists remove most large polyps, whether cancerous or not, to prevent them from developing into a cancer.
Colon and rectal cancer risk factors
The NCI says colorectal cancer is the fourth leading cause of cancer deaths among men and women in the U.S. Age is by far the greatest factor in who might get colorectal cancer and who might die from it.
Patients can’t control some risk factors, such as genetic conditions, but they can reduce some risk factors through their own actions. Doing such things as adjusting diet and stopping tobacco use help prevent colon and rectal cancer.
While anyone can get colon or rectal cancer, those with the following factors are at a higher risk:
- Over age 50
- Family history of colorectal cancer or polyps
- Inflammatory bowel disease such as Crohn’s disease or ulcerative colitis
- Inherited conditions such as familial adenomatous polyposis (FAP) or hereditary nonpolyposis colorectal caner (HNPCC)
- Type 2 diabetes
- A diet high in processed meat and/or red meat
- A diet high in fat and low in fiber
- Being African American or Native American
- Lifestyle factors including obesity, smoking, alcohol consumption and lack of physical activity.
Colon and rectal cancer symptoms
In many cases, colon or rectal cancer may not present any symptoms. When symptoms are present they may include:
- Changes in bowel movements, such as persistent diarrhea or constipation
- Blood in the stool
- Abdominal discomfort such as gas or cramps
- Unexplained weight loss
- Fatigue and weakness
Colon and rectal cancer screening and diagnosis
Colon and rectal cancers have a high cure rate if caught early. People younger than age 40 rarely get colorectal cancer. People with normal risk for colorectal cancer should begin screening around age 50. People with a high risk, such as those with family history or type 2 diabetes and colorectal cancers, should begin cancer screenings at age 45.
Colorectal cancer screenings may include the following:
- Physical exam
- Blood tests to determine kidney and liver health
- CT colonography, which is a noninvasive imaging test of the entire colon using a CT (computed tomography) scan. If a polyp or tumor is detected, a traditional colonoscopy must be administered.
- Colonoscopy, which involves a doctor using a thin, flexible tube with a light and camera to view the inside of the colon.
More detailed information about colorectal cancer screening and diagnosis is available.
Colon and rectal cancer treatments
If a polyp or tumor is found during screening, the doctor will remove the growth and send it to a laboratory for analysis. If the growth is confirmed as cancer, a number of treatments are available, including:
- Surgery for the removal of the growth
- Radiation therapy
Treatment of colorectal cancer will vary depending on the size, location and stage of the growth.
Contact cCARE if you think you may have colorectal cancer
The oncologists at California Cancer Associates for Research and Excellence (cCARE) are highly skilled in the diagnosis and treatment of colorectal cancer. If you have or think you may have colorectal cancer, request an appointment at cCARE today. For general questions about colorectal cancer contact us online.