Understanding Colon Cancer Screenings

Colorectal cancer is the third most common cancer in the United States. In 2021, an estimated 104,270 cases of colon cancer and 45,230 cases of rectal cancer will be diagnosed. Rates of colon and rectal cancer have been dropping in the past few decades due to more and more people getting preventative screenings and adopting lifestyle changes. The lifetime risk of developing colon cancer is 4% for women and 4.3% for men. It is the second most common cause of cancer deaths. Patients should start undergoing preventative screenings beginning at the age of fifty, even if they are not experiencing any symptoms. Those with a higher risk of developing colorectal cancer should talk to their doctor about when they should begin preventative screenings.

Symptoms of colorectal cancer can include changes in bowel habits, anemia, unexplained weight loss, diarrhea, constipation, fatigue, abdominal pain, bright red blood from the rectum, a feeling that the bowel is not emptied after bowel movements, and feeling full even after a long time has passed since a meal. Some patients only notice symptoms in the later stages of cancer, making screenings a crucial part of prevention.

How does colon cancer develop?

Colorectal cancer often starts as polyps, which are growths on the inner lining of the colon and rectum. Certain types of polyps can become cancerous over time. There are several different types which include adenomatous polyps, hyperplastic polyps, inflammatory polyps, sessile serrated polyps, and traditional serrated adenomas. If more than three polyps are found, if a polyp is larger than one centimeter, or if dysplasia is seen in the polyp, the patient’s risk of developing colorectal cancer can increase. Colorectal cancer starts in the mucosa, grows outward, and can travel to lymph nodes and the rest of the body. While most colorectal cancers are adenocarcinomas, other types of tumors that can start in the colon or rectum include carcinoid tumors, gastrointestinal stromal tumors, sarcomas, and lymphomas.

Getting Screened for Colorectal Cancer

Screenings for colorectal cancer can include stool-based tests and visual tests. Stool-based tests can include fecal immunochemical tests, guaiac-based fecal occult blood tests, and stool DNA testing. If any of these tests show abnormalities, a colonoscopy may be required. Visual tests such as a colonoscopy, CT colonography, and flexible sigmoidoscopy can be used to screen for colon cancer.  A colonoscopy is a procedure that involves a flexible, lighted tube that contains a small camera allowing the doctor to view the inside of the colon and rectum. Biopsies can also be taken during this procedure. A CT colonography is a scan of the rectum and colon that involves detailed images which can help detect polyps or cancer. A flexible sigmoidoscopy is not widely used as a preventative screening but can allow a doctor to view parts of the colon and rectum. If polyps or other abnormalities are detected during this procedure, the patient may also require a colonoscopy. Patients should talk to their doctor about when they should start preventive screenings for colorectal cancer and how often they need to repeat these screenings. Preventative screenings can detect cancer in the earlier stages, leading to better outcomes.

Contact the specialists at Granite State Gastroenterology to schedule your preventative screenings.