Upfront treatment of stage I-II NLPHL with RT/CMT is associated with excellent PFS
Acknowledging the excellent prognosis, the risk of late effects and potential for transformation should inform management decisions
Nodular lymphocyte-predominant Hodgkin lymphoma (NLPHL) is an uncommon histologic variant, and the optimal treatment for stage I-II NLPHL is undefined. We conducted a multicenter retrospective study including patients ≥16 years with stage I-II NLPHL diagnosed from 19952018 receiving all forms of management including radiotherapy (RT), combined modality therapy (CMT=RT+chemotherapy), chemotherapy (CT), observation after excision, rituximab and RT, and single agent rituximab (R). End points were progressionfree survival (PFS), freedom from transformation, and overall survival (OS) without statistical comparison between management groups. We identified 559 patients with median age 39 years, 72.3% being male, and 54.9% having stage I disease. Median follow up was 5.5 years (IQR=3.1-10.1). 5-year PFS and OS for the entire cohort were 87.1% (95%CI=83.6-90.0%) and 98.3% (95%CI=96.4-99.2%), respectively. Primary management was RT alone (n=257, 46.0%), CMT (n=184, 32.9%), CT alone (n=47, 8.4%), observation (n=37, 6.6%), rituximab and RT (n=19, 3.4%), and rituximab alone (n=15, 2.7%). 5-year PFS rates were 91.1% (95%CI=85.3-94.7%) after RT, 90.5% (95%CI=84.8-94.1%) after CMT, 77.8% (95%CI=61.3-88.0%) after chemotherapy, 73.5% (95%CI=50.6-87.0%) after observation, 80.8% (95%CI=41.0-95.1%) after rituximab and RT, and 38.5% (95%CI=14.0-62.8%) after rituximab alone. For the RT cohort but not the CMT cohort, variant immunoarchitectural pattern and number of sites>2 were associated with worse PFS (P<0.05). Overall, 21 patients (3.8%) developed large cell transformation, with a significantly higher transformation rate for those with variant immunoarchitectural pattern (P=0.049) and number of involved sites >2 (P=0.0006). OS for patients with stage I-II NLPHLwas excellent following all managements.