Patterns of Care and Clinical Outcomes in Systemic Peripheral T-cell Lymphoma: The LEO-MER Prospective Cohort Study

Few prospective benchmark studies exist to characterize the evolving contemporary real-world practice for PTCL. We report the patterns of first-line care and outcomes for 720 patients with systemic PTCL enrolled in two related prospective cohort studies, LEO from 2015-2020 (ClinicalTrials.gov NCT02736357) and MER from 2002-2015, both followed through 2024. The primary endpoints were EFS and OS using Kaplan-Meier estimator and Cox regression model. Secondary endpoints included correlations of clinical and treatment factors with survival. The most common induction regimens were CHOP-based (70%), given as CHOP (36%), CHOP plus etoposide (23%), or CHOP-like plus novel agents (11.5%, including 5% BV-CHP). Consolidative autologous stem cell transplant was performed in 102 patients (14%). Within nodal PTCL, EFS and OS were adversely associated with IPI 2-5 (HR=2.00, 95%CI: 1.59-2.52 for EFS; HR=2.44, 95%CI: 1.86-3.19 for OS), PIT 1-4 (HR=3.02, 95%CI 2.07-4.39 for EFS; HR=5.10, 95%CI 3.01-8.63 for OS), and non-ALCL subtypes (HR=2.97, 95%CI: 2.26-3.91 for EFS; HR=3.71, 95%CI: 2.65-5.20 for OS). Within LEO, which captured increasing first-line etoposide and BV, adding etoposide to CHOP was associated with better OS in ALK-negative ALCL (HR=0.14, 95%CI: 0.03-0.69, p=0.015). BV-CHP showed a trend toward OS improvement in ALCL (HR=0.15, 95%CI 0.02-1.19, p=0.073). Patients failing EFS6 and EFS24 had 5-year subsequent OS of 12% (95% CI: 7.8%, 19%) and 17% (95% CI: 13%, 22%), respectively. The inferior outcomes in non-ALCL subtypes and patients failing EFS6 and EFS24 highlight unmet needs with CHOP-based induction, where clinical trials with targeted therapy should be prioritized.