Treatment Patterns and Outcomes in Follicular Lymphoma with POD24: An Analysis from The LEO Consortium

• FL Patients who experience POD24 while retaining follicular histology have a short median EFS of 10.4 months, yet 5-year OS was 73%.

• Following POD24, cause of death in FL patients is predominantly due to lymphoma despite infrequent subsequent transformation events.

Progression of disease within 24 months of initial immunochemotherapy (POD24) is a negative prognostic factor for patients with follicular lymphoma (FL). There is no standard treatment following POD24. Assembling an academic-based cohort from the Lymphoma Epidemiology of Outcomes Consortium for Real World Evidence (LEO CREWE), we evaluated patterns of care and outcomes for 256 FL patients with POD24 and retained FL histology. Therapy after POD24 was heterogeneous, with no treatment category accounting for >25% of the total. Among patients initially treated with bendamustine-rituximab, R-CHOP was the predominant second-line choice (42%). Among patients initially treated with R-CHOP, the predominant second-line choice was aggressive salvage therapy (36%). Overall response rate to therapy following POD24 was 66% (95% confidence interval [CI] 59%-72%); complete response rate was 40% (95% CI 33%-46%). Median EFS for therapy after POD24 was 10.4 months (95% CI 8.4-12.8); 5-year OS was 73% (95% CI 68-80%). OS was inferior for patients aged >70 years (HR 2.31 [95% CI 1.27-4.20]) and those with high-risk FLIPI scores at diagnosis (HR 2.10 [95% CI 1.23-3.60]). Cause of death was predominantly lymphoma related. Patients with follicular histology at their POD24 event had a low cumulative incidence of transformation (1.9% at 5 years). Our study is among the largest cohorts describing contemporary patterns of care for patients with POD24, providing a focused dataset useful for interpreting and designing prospective clinical trials in this population.