Late morbidity and mortality after autologous blood or marrow transplantation for lymphoma in children, adolescents and young adults-a BMTSS report.

We determined the risk of late morbidity and mortality after autologous blood or marrow transplantation (BMT) for lymphoma performed before age 40. The cohort included autologous BMT recipients who had survived ≥2 years after transplantation (N = 583 [HL = 59.9%; NHL = 40.1%]) and a comparison cohort (N = 1070). Participants self-reported sociodemographics and chronic health conditions. A severity score (grade 3 [severe], 4 [life threatening] or 5 [fatal]) was assigned to the conditions using CTCAE v5.0. Logistic regression estimated the odds of grade 3-4 conditions in survivors vs. comparison subjects. Proportional subdistribution hazards models identified predictors of grade 3-5 conditions among BMT recipients. Median age at BMT was 30.0 years (range: 2.0-40.0) and median follow-up was 9.8 years (2.0-32.1). Survivors were at a 3-fold higher adjusted odds for grade 3-4 conditions (95% CI = 2.3-4.1) vs. comparison subjects. Factors associated with grade 3-5 conditions among BMT recipients included age at BMT (>30 years: adjusted hazard ratio [aHR] = 2.31; 95% CI = 1.27-4.19; reference: ≤21 years), pre-BMT radiation (aHR = 1.52; 95% CI = 1.13-2.03; reference: non-irradiated), and year of BMT (≥2000: aHR = 0.54; 95% CI = 0.34-0.85; reference: <1990). The 25 years cumulative incidence of relapse-related and non-relapse-related mortality was 18.2% and 25.9%, respectively. The high risk for late morbidity and mortality after autologous BMT for lymphoma performed at age <40 calls for long-term anticipatory risk-based follow-up.