Frontline Treatment Management for Patients With FL Reduces Risk of High-Grade Transformation to DLBCL

Frontline treatment management reduced the risk of high-grade transformation (HGT) to diffuse large B-cell lymphoma (DLBCL) among patients with follicular lymphoma (FL), but not marginal zone lymphoma (MZL), concluded a recent study.

“Follicular lymphoma and marginal zone lymphoma often have long overall survival (OS), however, high-grade transformation to diffuse large B-cell lymphoma markedly reduces survival,” stated lead study investigator Jorge Florindez, MD, Johns Hopkins University, Baltimore, Maryland and colleagues.

Investigators analyzed a SEER database which included patients diagnosed with FL grades 1 or 2 and MZL between 2000 and 2020. Fine and Gray models were utilized to estimate the impact of covariates on cumulative incidence and lymphoma-specific survival and Cox regression on OS. It was determined that HGT occurred in 4.2% of 23,384 patients with FL and 2.5% of 20,530 patients with MZL. The 5- and 10-year HGT cumulative incidence rates were 2.80% and 4.87% for patients with FL, and 1.74% and 2.95% for patients with MZL, respectively. Study authors noted these data were notably lower than in earlier studies. The annual HGT incidence rate peaked in the first 2 years, then steadily declined over 2 decades for FL and all MZL subtypes.

Results demonstrated that in FL, upfront observation versus treatment increases HGT risk ([subdistribution hazard ratio] SHR 1.23; 95% [confidence interval] CI: 1.09 to 1.40, P<0.001) and barely affects OS (HR 0.95; 95% CI, 0.90 to 0.99; P=0.03). However, upfront observation was associated with lower HGT risk in nodal (SHR 0.71; 95% CI: 0.53 to 0.94, P=0.01) and extranodal (SHR 0.64; 95% CI, 0.48 to 0.86; P=0.003) MZL and did not affect survival in extranodal disease (HR 0.94; 95% CI, 0.97 to 1.02; P=0.15).

“[High-grade transformation] was associated with decrease in [lymphoma-specific survival] across all histologies. Upfront treatment reduced the risk of HGT only in FL but not MZL,” concluded Dr Florindez and colleagues.

Source:

Florindez J, Chihara D, Reis I, et al. Risk of transformation by frontline management in follicular and marginal zone lymphomas: a US population-based analysis. Published online July 2, 2024. doi: 10.1182/bloodadvances.2024013499