SWOG S0016 follow-up data suggest a sustained cure fraction of 42% in advanced follicular lymphoma after initial chemoimmunotherapy, challenging the assumption that the disease is universally incurable. The report reflects a 15-year dataset showing an ongoing decline in annual relapse rates after the long-term mark. The analysis estimates a cured fraction for the overall cohort and reports that annual relapse risk drops to 0.6% beyond 15 years. Progression-free survival at 15 years was 34% in the R-CHOP arm, and the study also evaluated the effect of adding radioimmunotherapy. The trial’s CHOP plus radioimmunotherapy arm showed improved long-term progression-free survival versus R-CHOP alone, but no overall survival advantage was observed, and the combination carried a higher rate of myeloid neoplasms. For clinicians and product planners in hematology, the long-term cure framing can influence how treatment intensity, maintenance strategies, and emerging therapeutic positioning are discussed for later-line development and real-world expectations.