An analysis of the first generation of childhood cancer survivors, who are now aging into their fourth and fifth decades, shows further increases in the survivors’ morbidity and mortality risks. “By age 50 years, more than half of survivors have experienced a severe, disabling, or life-threatening event, including death,” Gregory T. Armstrong, MD, of St. Jude Children’s Research Hospital, Memphis, and colleagues wrote in the Journal of Clinical Oncology.1
The analyses compared the cumulative incidence of a severe, disabling, life-threatening, or fatal health condition among 14,359 patients from the Childhood Cancer Survivor Study and 4,301 of their siblings. The survivors had first been diagnosed when they were younger than 21 years old and received follow-up for a median of 24.5 years after diagnosis. Among the survivors, 5,604 were 35 years old or older, with a range up to 62 years.
“Compared with siblings, survivors had an increased cumulative incidence of severe, disabling, life-threatening, or fatal health conditions,” the investigators found. The increase in cumulative incidence at 20 years, which was 16% for cancer survivors vs 3.3% for siblings, increased with age and at 50 years was 53.6% for survivors vs 19.8% for siblings.
“Notably, 24-year-old survivors of childhood cancer had the same cumulative incidence of grade 3 to 5 health conditions (19.6%) as the 50-year-old siblings,” the investigators stated. Multivariable analysis confirmed that the hazard ratio (HR) for a severe, disabling, life-threatening, or fatal health condition “increased for survivors 35 years old and older compared with survivors 20 to 34 years old [HR = 5.0 vs 3.8; P = .03],” the researchers stated.
These findings have important implications for cancer screening and prevention. Though the cumulative incidence of events increased across all organ systems, after age 35 years survivors had a disproportionate increase in the incidence of subsequent malignant neoplasms and cardiac events. Although the occurrence of new malignancies has been well documented, we now demonstrate that this profound rise in incidence occurs during an important window of vulnerability, before the age-threshold when general population screening guidelines recommend screenings to start…. Similarly, early detection of cardiomyopathy and medical intervention may mitigate progression to heart failure in survivors exposed to anthracycline chemotherapy or chest directed radiotherapy. Finally, the risk for stroke and myocardial infarction, identified in this study to have increased more than fivefold in survivors older than 35 years, may be modified by promoting a healthy lifestyle that can reduce rates of certain … risk factors. ■
1. Armstrong GT, et al: J Clin Oncol 32:1218-1277, 2014.