Importance of colorectal cancer screening based on individual treatment exposures

Cancer survivors treated with abdomen, spine or pelvis radiation are at an increased risk of colorectal cancer.

Published: 07/25/2017

Cancer survivors and future colorectal cancer risk

Childhood cancer survivors treated with radiation to the abdomen, spine, or pelvis (hip area) have an increased risk of colorectal cancer. Colorectal cancer is highly treatable when found early. Yet only 30% of LTFU survivors at risk for colorectal cancer received the recommended screening for this disease.

Colon cancer is cancer of the large intestine (colon) which is the lower part of the digestive system. Rectal cancer is cancer of the last several inches of the colon. Together, they're often referred to as colorectal cancer. In the general population colorectal cancer is most likely to occur after age 50. In cancer survivors who were treated with abdominal, pelvic, or spinal radiation, the risk begins to increase much earlier, around 10 years after the radiation.

Colorectal cancer is the second leading cause of cancer death in the United States. However, if it’s found early enough it can usually be cured. If you are at risk, the best way to protect your health is to follow the recommended screening based on your specific treatment exposures. If you received radiation therapy to the abdomen, pelvis, or spine at doses of 30 Gy (3000 cGy/rads) or higher during childhood, adolescence, or young adulthood, you should have a colonoscopy at least every five years, starting at age 35, or 10 years after radiation (whichever occurs last).

We conducted a study that found that survivors who participated in long-term follow-up care that was focused on their childhood cancer were more likely to get their recommended health screenings, including colonoscopy. All survivors, especially those who don’t have the option of being cared for at a long-term follow-up clinic, should know the details of their treatment history and recommended screenings. If you don’t have one, ask for a summary of your treatment from the center where you were treated for your childhood cancer. Please share your treatment history with your doctor and make sure he or she is aware of the Children’s Oncology Group Survivorship Guidelines. The guidelines contain detailed risk-based health screening recommendations for survivors. They’re available online at


Predictors of colorectal cancer surveillance among survivors of childhood cancer treated with radiation: A report from the Childhood Cancer Survivor Study. Daniel CL, Kohler CL, Stratton KL, Oeffinger KC, Leisenring WM, Waterbor JW, Whelan KF, Armstrong GT, Henderson TO, Krull KR, Robison LL, Nathan PC. Cancer. 2015 Feb 3.