A B S T R A C T PurposeTwenty percent of patients with follicular lymphoma (FL) experience progression of disease (POD) within 2 years of initial chemoimmunotherapy. We analyzed data from the National LymphoCare Study to identify whether prognostic FL factors are associated with early POD and whether patients with early POD are at high risk for death. Patients and MethodsIn total, 588 patients with stage 2 to 4 FL received first-line rituximab plus cyclophosphamide, doxorubicin, vincristine, and prednisone (R-CHOP). Two groups were defined: patients with early POD 2 years or less after diagnosis and those without POD within 2 years, the reference group. An independent validation set, 147 patients with FL who received first-line R-CHOP, was analyzed for reproducibility. ResultsOf 588 patients, 19% (n ϭ 110) had early POD, 71% (n ϭ 420) were in the reference group, 8% (n ϭ 46) were lost to follow-up, and 2% (n ϭ 12) died without POD less than 2 years after diagnosis. Five-year overall survival was lower in the early-POD group than in the reference group (50% v 90%). This trend was maintained after we adjusted for FL International Prognostic Index (hazard ratio, 6.44; 95% CI, 4.33 to 9.58). Results were similar for the validation set (FL International Prognostic Index-adjusted hazard ratio, 19.8). ConclusionIn patients with FL who received first-line R-CHOP, POD within 2 years after diagnosis was associated with poor outcomes and should be further validated as a standard end point of chemoimmunotherapy trials of untreated FL. This high-risk FL population warrants further study in directed prospective clinical trials.

Key Points• The median posttransformation survival of 5 years suggests improved outcomes for transformed FL in the modern era.• Five-year progression-free and overall survival (66% and 88%) are favorable for patients with evidence of transformation at diagnosis.We assessed the incidence, prognostic features, and outcomes associated with transformation of follicular lymphoma (FL) among 2652 evaluable patients prospectively enrolled in the National LymphoCare Study. At a median follow-up of 6. , 83-86). The median overall survival posttransformation was 5 years. Forty-seven patients with evidence of transformation at the time of diagnosis shared similar prognostic factors and survival rates to those without transformation. Improved outcomes for transformation in the modern era are suggested by this observational study. This trial is registered at www.clinicaltrials.gov as #NCT00097565. (Blood. 2015;126(7):851-857)

In the setting of contemporary practice with routine R use, stratifying patients into good, intermediate, and poor FLIPI risk groups predicts distinct outcomes in terms of OS and PFS. FLIPI remains an important prognostic index in the R era and should be used in clinical practices to support discussions about prognosis.