Early-Stage Classic Hodgkin Lymphoma: The Utilization of Radiation Therapy and Its Impact on Overall Survival

Int J Radiat Oncol Biol Phys. 2015 Nov 1;93(3):684-93. doi: 10.1016/j.ijrobp.2015.06.039. Epub 2015 Jul 6.

Abstract

Purpose: To examine the association between radiation therapy (RT) utilization and overall survival (OS) for patients with early-stage Hodgkin lymphoma (HL).

Methods and materials: 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.

MeSH terms

  • Adult
  • Age Factors
  • Aged
  • Aged, 80 and over
  • Confidence Intervals
  • Disease-Free Survival
  • Female
  • Hodgkin Disease / mortality*
  • Hodgkin Disease / pathology
  • Hodgkin Disease / radiotherapy*
  • Humans
  • Male
  • Middle Aged
  • Propensity Score
  • Proportional Hazards Models
  • Radiotherapy / statistics & numerical data
  • Retrospective Studies
  • Socioeconomic Factors
  • Young Adult