Survival of Patients With Second Primary Hodgkin Lymphoma.

Introduction: The increased risk for second malignancies after Hodgkin lymphoma (HL) diagnosis is well known. However, to our knowledge, no study has investigated the outcomes of patients diagnosed with HL after an antecedent malignancy (HL-2). We aimed to investigate overall survival (OS), disease-specific survival (DSS), and correlates of survival in HL-2 using the Surveillance, Epidemiology and End Results (SEER) database. Patients and

Methods: HL-2 patients (n = 821) identified from the 2000-2014 SEER-18 registries were compared to first primary HL patients (HL-1, n = 31,355) from the same registries. Multivariable, propensity score-matched (PSM), and competing risks regression analyses were conducted to assess the effect of antecedent malignancy on survival.

Results: Hematologic (n = 309, 37.6%), prostate (n = 169, 20.6%), and breast (n = 76, 9.3%) malignancies were common antecedent malignancies in HL-2. Median latency between antecedent malignancy and HL diagnosis was 39 months. Median ages at HL diagnosis for HL-1 and HL-2 were 36 and 66 years, respectively (P < .001). The 5-year OS and HL-DSS rates for HL-2 versus HL-1 were 53.2% versus 82.7% and 79.1% versus 90.9%, respectively (P < .001). On multivariable analysis, antecedent malignancy was associated with decreased OS (hazard ratio [HR] = 1.27; 95% confidence interval [CI], 1.13-1.42; P < .001). With PSM balancing across covariables, antecedent malignancy was associated with decrements in HL-DSS (HR = 1.46; 95% CI, 1.12-1.92; P = .006) and OS (HR = 2.09; 95% CI, 1.74-2.51; P < .001).

Conclusion: The decrement in DSS in HL-2 relative to HL-1 may be related to biological differences in HL, age, and/or other unanalyzed factors. Further study of HL-2 patients is warranted.