Walter Reed National Military Medical Center, Md.  –   Colorectal Cancer Awareness Month, observed during March, seeks to increase the public’s knowledge about the disease and encourage people to get screened for it.

According to the American Cancer Society, estimates for the number of colorectal cancers in the United States for 2024 are about 106,590 news cases of colon cancer (54,210 in men and 52,380 in women), and about 46,220 news cases of rectal cancer (27,330 in men and 19,890 in women).

“The rate of people being diagnosed with colon and rectal cancers each year has dropped overall since the mid-1980s, mainly because more people are getting screened and changing their lifestyle-related risk factors,” the American Cancer Society added.

“The colon and rectum, also referred to as the large intestine, are the last several feet of the gastrointestinal tract and are responsible mostly for absorbing water prior to evacuation of stool. The human body is made up of cells that grow and divide regularly throughout our lives. Colorectal cancer (CRC) occurs when those cells in the large intestine begin to grow or divide abnormally, invade into the wall of the colon, and sometimes lymph nodes or other organs. CRC is often discovered on a colonoscopy, whether done for symptoms or as a screening exam, recommended for everyone at age 45,” stated Army Lt. Col. (Dr.) Mary O’Donnell, chief of colon and rectal surgery at Walter Reed National Military Medical Center (WRNMMC).

“People who are in good health and with a life expectancy of more and with a life expectancy of more than 10 years should continue regular colorectal cancer screening through age 75,” according to the American Cancer Society.

“Risk factors for colorectal cancer include increasing age, a family history of colorectal cancer or colon polyps, and diets high in animal fat and low in calcium, folate and fiber,” O’Donnell explained. She recommends people eat plenty of fruits and vegetables and avoid smoking and excessive alcohol use. “It’s recommended that adults eat 25 to 35 grams of fiber daily.”

“Unfortunately, colorectal cancer can often be asymptomatic,” O’Donnell explained. “This is why screening through procedures like colonoscopy are so important. The current recommendation for a person with no family history of colon or rectal cancer, or unknown history, is to receive their first screening exam for colorectal cancer at age 45.”

O’Donnell explained that symptoms of colorectal cancer could include, “but are not limited to,” blood in the stool, weight loss, changes in stool habits or caliber, constipation or feeling that the bowel does not empty completely, fatigue, anemia, abdominal pain or bloating, nausea, and vomiting.

The American Cancer Society shares that colorectal cancer disproportionately affects African Americans more than other ethnic groups. “In the United States, African Americans are about 20 percent more likely to get colorectal cancer and about 40 percent more likely to die from it than most other groups,” the society added.

“While the reasons for this are complex, access to health care exams and screening certainly contributes,” O’Donnell said. She shared that screening exams, like colonoscopy, are the best way to detect these cancers early or before polyps can become cancer.

“Colonoscopy allows your doctor to remove polyps, which, if left in place, may grow into cancer. All beneficiaries in our military health care system have access to this screening exam at age 45 or earlier if prescribed by your doctor. It is important to talk to your doctor about any symptoms you are having concerning CRC or if you have a family history of CRC or colon polyps,” O’Donnell stated.

“It is also important to note, especially in our military population, that older age is a risk factor for colon cancer, but 13 percent of Americans diagnosed with colorectal cancer in 2023 were under age 50. Talk to your doctor about a screening colonoscopy at age 45 or if you have concerning symptoms of CRC.”

“Luckily, much of colorectal cancer is preventable through screening exams like colonoscopy and sigmoidoscopy remove pre-cancerous polyps before they can grow into cancer,” O’Donnell continued. “Eat a diet low in animal fat and high in calcium, folate and fiber. Eat plenty of fruits and vegetables. It is also recommended that adults eat 25 to 35 grams of fiber daily, exercise regularly, do not smoke, and minimize alcohol intake.”

Although O’Donnell recommends people begin screening for colorectal cancer at age 45, she explains that if a person’s first-degree relative has had colorectal cancer, polyps run in their family, or there are other risk factors, screening may need to begin before 45.

She explained that small, early colon cancers can be treated by a gastroenterologist through advanced colonoscopy techniques. “The majority of colon cancers are treated through surgical removal of a portion of the colon and its associated lymph nodes. Chemotherapy can be necessary in addition to surgery based upon the stage of the cancer. Radiation and chemotherapy are often used to treat rectal cancers prior to surgery.”

“All of these services, wound ostomy care nursing, nutritionists and behavior health specialists in cancer-patient care are available at WRNMMC,” O’Donnell added. “The John P. Murtha Cancer Center at Walter Reed is nationally recognized by the American College of Surgeons and has been designated by the Assistant Secretary of Defense for Health Affairs as the only Department of Defense Cancer Center of Excellence.”

“One of the most common questions I get from patients is, ‘Will I need a bag?’ or ‘Do I have to have an ostomy bag?,’” O’Donnell continued. “This is one of the most feared risks of intestinal surgery that patients have in my clinic and often leads to the avoidance of a first colonoscopy in patients. It is important to know that needing an ostomy or stoma, where stool is emptied into a bag on the abdominal wall, is often not necessary in the treatment of these cancers. While we do create an ostomy during some of our surgical procedures, it is often temporary, to decrease the risks of a procedure. If an ostomy needs to be permanent to ensure the cure of a cancer, we have dedicated wound ostomy care nurses trained in helping patients adjust to having a stoma. Many people have completely normal lives with an ostomy bag and our goal is for the patient to be cancer free.”

O’Donnell encourages people to visit the Walter Reed colorectal surgery website for a list of conditions treated by her team and services offered. The website is located at walterreed.tricare.mil/Health-Services/Hospital-Care-Surgery/Colorectal-Surgery.