Long‐term cause‐specific mortality in adolescent and young adult Hodgkin lymphoma patients treated with contemporary regimens—A nationwide Danish cohort study

Summary The documented treatment‐induced excess mortality in Hodgkin lymphoma (HL) has spurred important treatment changes over recent decades. This study aimed to examine mortality among young HL patients treated with contemporary strategies, including historical data comparison. This nationwide study included 1348 HL patients, diagnosed in 1995–2015 and aged 15–40 at diagnosis. Among the patients, 66.5% had Ann Arbor stage I–II and 33.5% had stage III–IV disease. With a median follow‐up of 14.76 years, 139 deaths occurred, yielding a 5‐year overall survival of 94.6%. Older age, advanced disease, earlier treatment periods and extensive regimens were associated with higher overall mortality risk. The cumulative risk of HL‐related death showed an initial sharp rise, with a plateau at 5.3% 10‐year post‐diagnosis. Deaths due to cardiovascular or pulmonary diseases and second cancers initially had minimal risk, gradually reaching 1.2% and 2.0% at the 20‐year mark respectively. HL cases had a 7.5‐fold higher mortality hazard than the background population. This study suggests that contemporary HL treatment still poses excess mortality risk, but recent changes have notably reduced overall and cause‐specific mortality compared to earlier eras. Balancing treatment efficacy and toxicity remains crucial, but our findings highlight improved outcomes with modern treatment approaches. The therapeutic paradigm in Hodgkin lymphoma has shifted. Study of long‐term cause‐specific mortality in Danish patients show that we cure more patients and see less treatment‐related mortality.