Purpose: In 2018, a "survival cliff" in the United States was identified among older adolescent and young adult (AYA) patients with acute lymphoblastic leukemia (ALL) and lymphoblastic lymphoma (LBL). This study reassessed the cliff and associated putative causes. Methods: Survival data were obtained using the U.S. Surveillance Research Program, National Cancer Institute (NCI) SEER 22 Registries. Accrual data on cancer treatment trials conducted by the NCI cooperative groups and NCI-designated cancer centers were obtained from the NCI Cancer Therapy Evaluation Program. Trend and average percent changes and statistical significances were identified with the NCI Joinpoint Regression Program. Results: A previous cliff-like decrement in the survival of 17- to 20-year-olds is no longer apparent, overall and in all racial and ethnic groups. The "survival cliff" age range was coincident with a clinical trial accrual cliff, and both diminished when more clinical trials were available to, and participated in by, young adult patients. Older AYA patients of ages 30-39 had minimal improvement in clinical trial accrual and least survival gain among the AYA age group. Conclusion: The survival cliff has abated, resulting in thousands of fewer premature deaths and tens of thousands of years of life saved-a remarkable achievement. The survival improvement may be attributed to improved clinical trial availability for and recruitment and participation of AYAs on treatment trials, application of pediatric-inspired ALL treatment regimens to AYAs, expanded national health insurance for -18 to 25 year olds, improved AYA cancer services, and a national focus on AYA oncology.
Keywords: adolescents and young adults; clinical trials; survival progress.