Background: Childhood cancer survivors treated with radiotherapy to a field including the colon or rectum have an elevated risk of developing radiation-induced colorectal cancer (CRC). The Children's Oncology Group recommends colonoscopy every 5 years beginning at age 35 years for at-risk survivors.
Methods: Analyses included 702 five-year survivors (Childhood Cancer Survivor Study) aged ≥36 years who received ≥30 gray of abdominal, pelvic, or spinal radiotherapy. Multivariate generalized linear models were used to calculate relative risks (RR) with 95% confidence intervals (95% CI) for adherence to the Children's Oncology Group's CRC surveillance recommendations.
Results: With a median age of 43 years (range, 36-58 years), 29.5% of the survivors (207 of 702 survivors) met surveillance recommendations. In multivariate analyses, age ≥50 years versus age 36 to 49 years (RR, 2.6; 95% CI, 2.0-3.4), reporting a routine cancer follow-up visit within 1 year before the study (RR, 1.5; 95% CI, 1.0-2.2), reporting ≥10 physician visits within the past year versus 0 to 9 visits (RR, 1.4; 95% CI, 1.1-1.7), and discussing future cancer risk with a physician at the time of the most recent follow-up visit (RR, 1.4; 95% CI, 1.1-1.7) were found to be associated with adherence to CRC surveillance recommendations.
Conclusions: Greater than 70% of survivors at an increased risk of CRC were not screened as recommended. Regular physician contact and discussion of screening were associated with a 60% increase in CRC surveillance. Educational interventions targeted at survivors and their primary care physicians are needed to heighten knowledge of CRC risk after radiotherapy and the importance of appropriate surveillance.
Keywords: childhood cancer; colorectal; screening; survivor.
© 2015 American Cancer Society.