ASCO: Childhood Cancer Tied to Long-Term Cancer Risk
Increased risk of subsequent digestive and genitourinary neoplasms in survivors 40 or older
MONDAY, June 6 (HealthDay News) -- Childhood cancer survivors have an increased risk of developing subsequent digestive and genitourinary primary neoplasms after the age of 40, according to a study published in the June 8 cancer-themed issue of the Journal of the American Medical Association to coincide with the annual meeting of the American Society of Clinical Oncology, held from June 3 to 7 in Chicago.
Raoul C. Reulen, Ph.D., from the University of Birmingham in the United Kingdom, and colleagues investigated the long-term risks of subsequent primary neoplasms in 17,981 five-year survivors of childhood cancer. Participants were diagnosed with cancer before the age of 15 years, between 1940 and 1991, and were followed up through 2006. The different types of subsequent primary neoplasms were correlated with long-term excess risk. Standardized incidence ratios (SIRs), absolute excess risks (AERs), and cumulative incidence of subsequent primary neoplasms were the primary outcomes measured.
The investigators identified 1,354 subsequent primary neoplasms, most frequently in the central nervous system, skin (nonmelanoma skin cancer), digestive tract, genitourinary system, breast, and bone. An almost four-fold increase was seen in the overall SIR (3.9), with an AER of 16.8 cases per 10,000 persons. For individuals older than 40, the AER for subsequent primary digestive and genitourinary neoplasms was 5.9 and 6.0 per 10,000 years, respectively, cumulatively accounting for 36 percent of all subsequent primary neoplasms. The cumulative incidence of colorectal cancer was comparable for survivors treated with direct abdominopelvic irradiation by age 50 years and individuals with at least two first-degree relatives with colorectal cancer.
"The greatest excess risk associated with subsequent primary neoplasms at older than 40 years was for digestive and genitourinary neoplasms," the authors write.