Long-Term Outcomes in Patients with Early Stage Nodular Lymphocyte-Predominant Hodgkin’s Lymphoma Treated with Radiotherapy

PURPOSE: Radiation therapy (RT) is commonly used as definitive treatment for early-stage nodular lymphocyte-predominant Hodgkin’s lymphoma (NLPHL). We evaluated the cause-specific survival (CSS), overall survival (OS), and second malignancy (SM) rates in patients with early-stage NLPHL treated with RT. METHODS AND MATERIALS: Patients with stage I-II NLPHL between 1988 and 2009 who underwent RT were selected from the Surveillance, Epidemiology and End Results database. Univariate analysis (UVA) for CSS and Os was performed using the Kaplan-Meier method and included age, gender, involved site, year of diagnosis, presence of B-symptoms, and extranodal involvement (ENI). Multivariable analysis (MVA) was performed using Cox Proportional Hazards modeling and included the above clinical variables. SM were classified as RT-related or non-RT-related. Freedom from SM and freedom from RT-related SM were determined using the Kaplan-Meier method. RESULTS: The study cohort included 469 patients. Median age was 37 years. The most common involved sites were the head and neck (36%), axilla/arm (26%), and multiple lymph node regions (18%). Sixty-eight percent had stage I disease, 70% were male, 4% had ENI, and 7% had B-symptoms. Median follow-up was 6 years. Ten-year CSS and Os were 98% and 88%, respectively. On UVA, none of the covariates was associated with CSS. Increasing age (p<0.01) and female gender (p<0.01) were associated with worse Os. On MVA, older age (p<0.01), female gender (p=0.04), multiple regions of involvement (p=0.03), stage I disease (p=0.02), and presence of B-symptoms (p=0.02) were associated with worse Os. Ten-year freedom from SM and freedom from RT-related SM were 89% and 99%, respectively. CONCLUSIONS: This is the largest series to evaluate the outcomes of stage I-II NLPHL patients treated with RT and found that this patient population has an excellent long-term prognosis and a low rate of RT-related second malignancies.