Adolescent and young adult cancer survivors have a 73% higher risk for endocrine diseases than the cancer-free population, according to a study published in JAMA (online: June 29, 2018; doi:10.1001/jamanetworkopen.2018.0349).

Mette Vestergaard Jensen, MD, Danish Cancer Society Research Center (Copenhagen, Denmark), and colleagues investigated the lifetime risks of endocrine late effects of cancer and cancer treatment in adolescent and young adult survivors of cancer. 

This nationwide, population-based cohort study conducted in Denmark included a total of 32,548 1-year cancer survivors diagnosed at ages 15 to 39 years. The study took place from January 1, 1976, through December 31, 2009, with follow-up through December 31, 2010. Patients were identified using the Danish Cancer Registry and 188,728 cancer-free participants matched by year of birth and sex were randomly chosen from the Danish Civil Registration system for comparison. 

Authors noted that all hospital contacts for endocrine diseases were identified by linkage to the National Patient Register. Standard hospitalization rate ratios (RRs) and absolute excess risks (AERs) were calculated.

Researchers reported that a total of 2129 survivors (6.5%) had at least one hospital contact for an endocrine disease, showing a statistically significant increased RR of 1.73 (95% CI, 1.65-1.81) over the 1232 survivors (3.8%) expected. The highest reported RRs were for testicular hypofunction (75.12; 95% CI, 45.99-122.70), ovarian hypofunction (14.65; 95% CI, 8.29-25.86), and pituitary hypofunction (11.14; 95% CI, 8.09-15.34). 

Additionally, researchers reported that thyroid disease (38.0% of total AER), testicular dysfunction (17.1% of total AER), and diabetes (14.4% of total AER) were the leading causes for hospital contacts. Leukemia survivors were at a high risk for any endocrine disease (RR, 3.97; 95% CI, 3.10-5.09), while Hodgkin lymphoma survivors (RR, 3.06; 95% CI, 2.62-3.57) had the highest disease-specific excess risk for hypothyroidism (AER, 362 per 100 000 person-years; 95% CI, 280-443 per 100 000 person-years).

“The increased risk for endocrine diseases in adolescent and young adult cancer survivors indicates the need for counseling and follow-up, and could guide future preventive measures and surveillance strategies,” authors concluded. “Additional studies are required to determine exact associations between treatment regimens and endocrine diseases.”—Janelle Bradley