Regular screening can help prevent colorectal cancer

March is the harbinger of spring. It also marks the observance of National Colorectal Cancer Awareness Month. Cancer of the colon and rectum, collectively termed colorectal cancer, is the third most common cancer in this country in both men and women, and the second leading cause of cancer-related deaths.

According to the American Cancer Society (ACS), almost 137,000 new cases of colorectal cancer and 50,000 deaths are estimated for 2014. Actually, that is good news. The ACS notes that the incidence and death rates from colorectal cancer have been decreasing for the past 20 years, largely due to an uptick in screening.

The exact cause of colorectal cancer is not known. But what is known are the many conditions that increase one’s risk for the disease. Age, family or personal history of colorectal cancer, certain genetic conditions, and a history of colon polyps are factors. Those with inflammatory intestinal disorders, such as Crohn’s disease or ulcerative colitis, are also prone.

Polyps, or growths on the inner wall of the large intestine, are common in people over the age of 50. Many of these growths are actually pre-malignant lesions that have a long latency period. If left alone, they can eventually turn into cancer.

Polyps are found and removed during a screening test — more commonly a colonoscopy — in which a lighted tube is inserted into the entire length of the colon and rectum. Since it is not known which polyps will become cancerous, all are removed when detected.

The signs and symptoms of colorectal cancer are varied, but the two strong telltale signs are blood in the stool and a change in bowel habits, such as diarrhea or constipation. Other symptoms may include abdominal pain, fatigue or weight loss with no known reason.

Sometimes there are no symptoms at all. Colorectal cancer is generally silent in the early stages and causes symptoms when it advances. That is why screening is key. If polyps are found and removed during screening, colorectal cancer, unlike most other cancers, can often be prevented. It can also be treated more successfully when found early.

According to the National Cancer Institute, when colorectal cancer is found in the early stages, the five-year survival rate is 90 percent. When it has spread to distant parts of the body, the rate drops to 13 percent.

Massachusetts boasts one of the highest percentages of eligible residents screened. In 2012, almost 70 percent of the state’s adults aged 50 years and older who were surveyed said they have had a sigmoidoscopy or colonoscopy — two screening tests for colorectal cancer. An encouraging note is that more than 67 percent of blacks interviewed reported to have been screened. The Incidence and death rates of colorectal cancer are higher in African Americans than in any other race.

The ACS recommends that people of average risk for colorectal cancer should begin screening at age 50. . The American College of Gastroenterology, however, recommends that African Americans of average risk should begin screening at age 45. People of high risk, such as those with a familial history of the disease, should begin at an earlier age. Your doctor will recommend a schedule that takes into account your risk factors.

There are many screening tests available. Fecal occult blood test looks for blood in the stool, which may be an indicator of cancer, while the barium enema, sigmoidoscopy and colonoscopy look for polyps and cancer.

For many gastroenterologists, doctors that focus on the digestive system and its disorders, colonoscopy is the gold standard. Many cases of colon cancer begin in the right side of the large intestine, a section the sigmoidoscopy misses. A saying oft repeated is that a sigmoidoscopy is like a mammogram on one breast. In addition, a colonoscopy is still required if the sigmoidoscopy or other tests are positive.

While the preparation for a colonoscopy is still a deterrent for most people — the bowels must be completely cleared — cost has become less of a barrier to colorectal screening. The Affordable Care Act, more affectionately known as “Obamacare,” requires coverage of colorectal cancer screening tests at no expense to patients by health plans that started on or after September 23, 2010. Health plans in effect prior to that date are more often under state, rather than federal mandates. Medicare also covers colorectal screening at no cost.

Lifestyle also plays a part in reducing the risk of colorectal cancer. Some research has shown that diets high in fatty red meats and processed meats, such as bacon, ham and sausage, can increase a person’s risk for colon cancer. Lack of exercise, obesity, smoking and alcohol use may also pose a risk.

But health experts are quick to point out that lifestyle changes do not take the place of colonoscopy. Eating well does not mean you can’t get cancer.