Survival of Adolescents and Young Adults with Prevalent Poor-Prognosis Metastatic Cancers: A Population-Based Study of Contemporary Patterns and Their Implications

Abstract

Background: Although survival has improved dramatically for most adolescents and young adults (AYA; 15-39 years old) with cancer, it remains poor for those presenting with metastatic disease. To better characterize this subset, we conducted a landscape survival comparison with older adults (40-79 years). Methods: Using Surveillance, Epidemiology, and End Results Program data from 2000 to 2016, we examined incident cases of poor-prognosis metastatic cancers (5-year survival < 50%) among AYAs (n = 11,518) and older adults (n = 345,681) and compared cause-specific survival by sociodemographic characteristics (race/ethnicity, sex, and socioeconomic status). Adjusted HRs (aHR) for death from metastatic disease [95% confidence intervals (95% CI)] were compared between AYAs and older adults (Pint). Results: AYAs had significantly better survival than older adults for every cancer site except kidney, where it was equivalent (range of aHRs = 0.91; 95% CI, 0.82-1.02 for kidney cancer to aHR = 0.33; 95% CI, 0.26-0.42 for rhabdomyosarcoma). Compared with their older adult counterparts, greater survival disparities existed for AYAs who were non-Hispanic Black with uterine cancer (aHR = 2.20; 95% CI, 1.25-3.86 versus aHR = 1.40; 95% CI, 1.28-1.54; Pint = 0.049) and kidney cancer (aHR = 1.51; 95% CI, 1.15-1.98 versus aHR = 1.10; 95% CI, 1.03-1.17; Pint = 0.04); non- Hispanic Asian/Pacific Islanders with ovarian cancer (aHR = 1.47; 95% CI, 1.12-1.93 versus aHR = 0.89; 95% CI, 0.84-0.95; Pint<0.001); and males with colorectal cancer (aHR = 1.21; 95% CI, 1.10-1.32 versus aHR = 1.08; 95% CI, 1.06-1.10; Pint = 0.045). Conclusions: AYAs diagnosed with these metastatic cancers have better survival than older adults, but outcomes remain dismal.