Early-Stage Classic Hodgkin Lymphoma: The Utilization of Radiation Therapy and Its Impact on Overall Survival.
OBJECTIVE
To examine the association between radiation therapy (RT) utilization and overall survival (OS) for patients with early-stage Hodgkin lymphoma (HL).


METHODS
Using the National Cancer Database, we evaluated clinical features and survival outcomes among patients diagnosed with stage I/II HL from 1998 to 2011. The association between RT use, covariables, and outcome was assessed in a Cox proportional hazards regression model. Propensity score matching was performed to balance observed confounding factors. Survival was estimated using the Kaplan-Meier method.


RESULTS
Among the 41,943 patients in the National Cancer Database with stage I/II HL, 29,752 patients were analyzed for this study. Radiation therapy use was associated with younger age (≤40 years), favorable insured status, higher socioeconomic status (income, education), and treatment at comprehensive community cancer centers (all P<.05). Five-year OS for patients receiving RT was 94.5%, versus 88.9% for those not receiving RT (P<.01). Radiation therapy use was a significant predictor of OS in the "As-Treated" cohort (hazard ratio 0.53, 95% confidence interval 0.49-0.58, P<.01) and intention-to-treat analysis (P<.01). After propensity score matching based on clinicopathologic characteristics, RT use remained associated with improved OS (hazard ratio 0.46, 95% confidence interval 0.38-0.56, P<.01). Over the study period, RT utilization for this cohort decreased from 55% to 44%, most commonly because it was not part of the planned initial treatment strategy.


CONCLUSIONS
Consolidation RT was associated with improved OS for patients with early-stage classic HL. We also have identified patient-specific variations in the use of RT that may be targeted to improve patient access to care.
Department of Radiation Oncology, Mount Sinai Beth Israel Medical Center and Mount Sinai St. Luke's-Roosevelt Hospitals, Mount Sinai Health System, Icahn School of Medicine at Mount Sinai, New York, New York. Electronic address: rparikh@chpnet.org.
Rahul R
RR
Parikh
Division of Hematology-Oncology, Laura and Isaac Perlmutter Cancer Center, New York University Langone Medical Center, New York, New York.
Michael L
ML
Grossbard
Department of Radiation Oncology, Moffitt Cancer Center and Research Institute, Tampa, Florida.
Louis B
LB
Harrison
Department of Radiation Oncology, Memorial Sloan-Kettering Cancer Center, New York, New York.
Joachim
J
Yahalom
D000328:Adult; D000367:Age Factors; D000368:Aged; D000369:Aged, 80 and over; D016001:Confidence Intervals; D018572:Disease-Free Survival; D005260:Female; D006689:Hodgkin Disease / Q000401:mortality* / Q000473:pathology / Q000532:radiotherapy*; D006801:Humans; D008297:Male; D008875:Middle Aged; D057216:Propensity Score; D016016:Proportional Hazards Models; D011878:Radiotherapy / Q000706:statistics & numerical data; D012189:Retrospective Studies; D012959:Socioeconomic Factors; D055815:Young Adult