TREATMENT PATTERNS IN PATIENTS WITH MANTLE CELL LYMPHOMA: UPDATED REPORT OF THE ASIA‐PACIFIC MULTINATIONAL RETROSPECTIVE REGISTRY STUDY

Abstract

Introduction: We conducted a multinational, multicenter retrospective registry study to better define the treatment patterns and survival outcomes of newly diagnosed patients with mantle cell lymphoma (MCL) in the Asia-Pacific region. Methods: Data were collected from newly diagnosed MCL patients between January 2008 and September 2019 from 27 hospitals in Asian countries, including China, Malaysia, Japan, Singapore, South Korea, Taiwan, and Thailand. The first interim analysis with 191 patients was previously reported. An updated analysis of 289 patients was performed at the data cutoff date of December 19, 2022. Results: The median age was 64 years (range, 26–90), and 213 patients were male (73.7%). The majority of the patients had stage 3 or 4 diseases (n = 249, 86.2%). The most frequently administered 1st line regimen was R-CHOP or R-CHOP-like regimens (n = 146), followed by cytarabine-containing regimens (n = 78) including R-Hyper-CVAD (n = 56), and bendamustine-rituximab (n = 22) (Figure 1A). Higher proportion of elderly patients received R-CHOP or R-CHOP-like regimens, while cytarabine-containing regimens were more frequently administered in young patients (Figure 1B). The overall response rate (ORR) and the complete response (CR) rate among these patients were 94.7% and 59.0%, respectively. The ORR and CR rates for each regimen were as follows; R-CHOP or R-CHOP-like regimens (ORR 97.0%, CR 52.2%), cytarabine-containing regimens (ORR 94.6%, CR 65.3%), and bendamustine-rituximab (ORR 95.2%, CR 76.2%). Median progression-free survival (PFS) was 47.6 months, and median overall survival (OS) was 75.7 months. The median PFS was 41.1 months for R-CHOP or R-CHOP-like regimens, 60.8 months for cytarabine-containing regimens, and 71.0 months for bendamustine-rituximab. Twenty-nine patients received rituximab maintenance treatment, and the survival outcomes regarding maintenance therapy will be updated and presented at the ICML 2023. There were no significant differences in PFS and OS between the ASCT (n = 103) and non-ASCT (n = 35) groups among transplant-eligible patients (n=138), with a 5-year PFS rate of 48.6 versus 32.5% (P = 0.29) and 5-year OS rate of 73.7 versus 73.7% (P= 0.13), respectively. A total of 152 patients were given the 2nd line regimens. The most commonly used regimen was ibrutinib (n = 45), followed by cytarabine-based regimens (n = 38). The median 2nd PFS was 17.3 months. Keyword: Aggressive B-cell non-Hodgkin lymphoma The research was funded by: The work was funded by a research grant from Janssen Pharmaceuticals Ltd. No conflicts of interests pertinent to the abstract.