INTRODUCTION: Despite gains in survival for patients (pts) with follicular lymphoma (FL) who receive aggressive treatments, such as R-CHOP (rituximab with cyclophosphamide, doxorubicin, vincristine, and prednisone) and rituximab maintenance, 20% of pts experience progression of disease (POD) within 2 years (y) of chemoimmunotherapy, as shown by PRIMA and others. We analyzed the data from the National LymphoCare Study to identify FL pts at high risk for death after R-CHOP treatment and to identify factors associated with high-risk FL.
METHODS: Evaluable pts had stage 2–4 FL treated with first-line R-CHOP. Pts were excluded if initially observed or if POD was before first-line treatment. Two groups were defined: pts with POD/death ≤2 y from diagnosis (early POD) and a reference group without POD/death within 2 y (Ref). Multiple logistic regression compared baseline characteristics by group. Survival probability was estimated by the Kaplan-Meier method. A Cox model evaluated the impact of early and late POD (>2 y) on overall survival (OS).
RESULTS: 589 pts were analyzed. Within the first 2 y, 21% of pts (n=122) had early POD vs 71% (n=421) in the Ref group; 8% (n=46) were lost to follow-up within 2 y without POD. OS at 5 y in the early POD group was 50%; in the Ref group, it was 95%. For early POD pts alive at 2 y, OS was 71% (Table 1). Early POD was significantly associated with worse OS, with hazard ratios of 12.8 (95% CI 7.6–21.5) vs pts not progressing. After adjusting for early/late POD, age and ECOG performance status (PS) were associated with worse OS. High LDH, poor ECOG PS, B symptoms, and bone marrow (BM) involvement were associated with early POD (P<0.05).
CONCLUSIONS: Relapse of FL within 2 y of initial R-CHOP defines a unique category of pts at substantially increased mortality risk. High LDH, poor ECOG PS, B symptoms, and BM involvement conferred a high risk for early POD. These high-risk pts represent a distinct population warranting further study in directed prospective clinical trials.
