Interim PET response of Pola-R-CHP predicts outcome in previously untreated CD5-positive diffuse large B-cell lymphoma: a multicenter retrospective study

Background CD5-positive diffuse large B-cell lymphoma (DLBCL) is an aggressive subtype with poor outcomes. Following the approval of Pola-R-CHP in China, this study aimed to evaluate its efficacy as initial therapy for this high-risk population.Methods We conducted a multicenter, retrospective study of previously untreated CD5-positive DLBCL patients who received Pola-R-CHP as first-line therapy between April 2023 and February 2025. Treatment response was assessed by PET/CT after 3 cycles and at the end of treatment.Results Among 32 enrolled patients (median age 63.5 years), 78.1% had stage III–IV disease and 59.4% had an International Prognostic Index score ≥3. The overall response rate (ORR) was 100% after 3 cycles, with a complete response rate (CRR) of 71.9%. At end of treatment, the ORR and CRR were 93.8% and 75%, respectively. After a median follow-up of 17.9 months, 2-year progression-free survival (PFS) and overall survival rates (OS) were 70% and 82.7%. After adjusting covariates, failure to achieve a complete response (CR) after 3 cycles was a predictor of inferior survival [PFS HR: 18.1, p = 0.02; OS HR: 12.3, p = 0.033]. Grade 3–4 adverse events occurred in 31.3% of patients, with neutropenia being most common.Conclusions CD5-positive DLBCL patients exhibited rapid and promising responses to first-line Pola-R-CHP with an acceptable safety profile. Interim response assessment is a potential prognostic factor. In instances where CR is not attained by the interim PET/CT, it is advisable to consider treatment modification, as this may indicate a potential failure to achieve CR.