Clinical Characteristics and Initial Treatment Patterns of Mantle Cell Lymphoma in Btki Era: A Multi-Center Real-World Study in China
Authors: Cong Mengya , Jia Junlei , Liang Zhanli , Cao Luming , Zhang Huilai , Li Wenyu , Bai Ou , Huang Haiwen 
Published: December 2024

Objective:

Mantle cell lymphoma (MCL) is a heterogeneous and incurable type of lymphoma with highly varied clinical courses. Treatment strategies for MCL had evolved rapidly during the last five years, with Bruton's tyrosine kinase (BTK) inhibitors now being integrated into real-world practice. The aim of the study was to outline the disease characteristics, initial treatment patterns, and survival in patients with MCL managed in the real world.

Methods:

We conducted a retrospective review of MCL patients treated at multi-centers between January 2017 and December 2022, clinical data included patients who received treatment for the first time and had complete treatment records were collected in this study. All data were analyzed using SPSS26.0.

Results: General information and clinical presentation: Data of 190 newly diagnosed MCL patients were retrospectively analyzed. There were 161 (84.7%) males and 29(15.3%) females, resulting in amale-to-female ratio of 5.55:1. The age at diagnosis ranged from 23 to 84 years, with a median age of 62 years (range: 23-84). A majority of patients (52.6%) were older than 60 years. Of all patients, 19(10.0%) had ECOG PS ＞1 and 133 (80.7%) were diagnosed with Ann Arbor stage III-IV disease.108 (56.8%) had intermediate- and high-risk Mantle Cell Lymphoma International Prognostic Index (MIPI) scores. B symptoms were present in 120 (63.2%) patients, and bone marrow involvement was observed in 96 (50.5%) patients at the time of diagnosis. 66 (34.7%) had elevated LDH. Ki67 expression was ≥30% in 63.2% of the patients. A total of 90 patients (47.4%) achieved CR after induction chemotherapy. Treatment description and efficacy analysis: within the entire cohort, 175(92.1%) of patients received rituximab as their first-line therapy. A total of 70(36.8%) patients were treated with BTKi-containing chemotherapy. Besides the BTKi-containing chemotherapy, the most frequently used chemotherapy regimens were the CHOP-like (cyclophosphamide, hydroxydaunomycin, oncovin, and prednisone) regimen (30.5%), and cytarabine-containing regimens(24.2%). DHAP (dexamethasone, cytarabine, and cisplatin) was the most common cytarabine-containing regimen, administered in 41 cases. Other regimens, such as bendamustine-based and CVP-like (cyclophosphamide, vincristine, and prednisolone), were each used in fewer than 5% of cases. A total of 31 patients (16.3%) received ASCT as consolidation therapy. The inclusion of rituximab had a statistically significant effect on OS and PFS(OS:P=0.01;PFS:P=0.01). BTKi-containing chemotherapy demonstrated significant clinical benefit on OS and PFS (OS:P＝0.040;PF:P=0.020). ASCT as consolidation treatment improved the OS and PFS, with borderline significance(OS: P＝0.082; PFS: P＝0.069). Our analysis did not show significant difference in patients receiving induction therapy with BTKi-based regimens followed by ASCT than induction therapy with BTKi-based regimens without subsequent ASCT(P=0.422). Survival and prognostic analysis: The median follow-up was 29 months (range: 0-84 months). The 1-year and 2-year OS rates were 80.0% and 75.0%, respectively. The 1- and 2-year PFS rates were 77.0% and 69.0%, respectively. Pre-treatment factorssuch as age, ECOG score, disease stage, plasma LDH level, sMIPI score all significantly impacted OS and PFS (P &lt; 0.05). Further Cox regression analysis of 190 MCL patients revealed that age &gt;60 years, Ki67 ≥30%, and failure to achieve complete remission (CR) after induction chemotherapy were independent risk factors affecting both OS and PFS.

Conclusions: The general conditions of patients before treatment, such as young age, low ECOG score，stages I-II, low plasma LDH，Ki67&lt;30% and lower-risk MIPI scores, were signiﬁcantly associated with improved OS and PFS(p&lt;0.05). Multivariate Cox regression analysis showed that age ＞60 years, Ki67≥30% and patients who didn't achieve CR after induction chemotherapy were independent risk factors affecting OS and PFS. The inclusion of rituximab showed signiﬁcant clinical beneﬁt on OS. For newly diagnosed MCL patients, BTKi-containing chemotherapy was an effective treatment. ASCT as consolidation treatment improved the OS, with borderline significance. For patients receiving BTKi-containing chemotherapy, there was no significant difference in overall survival rate whether they received subsequent ASCT.