Clinical Characteristics, Treatment and Outcome of Patients with Mantle Cell Lymphoma: A Large, Multicenter Retrospective Analysis in China
Authors: Yang Ping , Liu Shuozi , Wang Jing , Zhang Wei , Liu Hui , Sun Xiuhua , Dong Yujun , Jing Hongmei 
Published: November 2021

Abstract
Background Mantle cell lymphoma (MCL) is an uncommon heterogeneous subtype of B cell non-Hodgkin lymphoma, most MCL cases have a rapid evolution and an aggressive behavior with an unfavorable outcome. Clinical features in mantle cell lymphoma appeared regional characteristics and the epidemiology of MCL in Asia is not accurate documented. MCL treatment opinions are not uniform between country/region within Asia and China. At present, the large-scale Asian patient-specific data for the treatment of MCL are lacking.
Aims To obtain 'real world' clinical characteristics,treatment patterns and prognosis factors of MCL patients in China and to address the knowledge gap in Chinese MCL patients.
Methods Patients diagnosed with MCL between April 1999 and December 2019 at 19 comprehensive hospitals in China were included in this retrospective analysis. The median follow-up times was 36.0 months. The data of total 805 patients with mantle cell lymphoma were collected, 112 patients with incomplete clinical data, no chemotherapy and missing follow-up data were excluded. Finally, 693 patients with complete clinical data, treatment information and survival follow-up data were included in this study.Fully detailed information of patients, disease characteristics, treatments and outcomes were collected. Fisher's exact test or Pearson's Chi-squared test were used to compare categorical variables.Survival analysis was performed by Kaplan-Meier.
Results The median age of the cohort was 60.0 years with a male-to-female ratio of 3.36:1. 477 patients (68.8%) were younger than 65 years at diagnosis.Advanced stage of diseases were 90.0%. Extranodal organ involvement was 83.4% and the most frequently involved extranodal organs were bone marrow(46.2%), spleen(36.1%), gastrointestinal tract(24.8) and oropharynx(17.7%). Blastic/pleomorphic mantle cell lymphoma accounted for 12.8%, and non-nodular mantle cell lymphoma accounted for 3.3%. Ki-67 more than 30% was 57.7% and Ki-67 ≥ 50% was 26.1%. The intermediate /high risk group was 49.8% according to MIPI score. The first-line therapeutic schedule is not completely unified, the most frequently regimen was CHOP/CHOP-like±R (n=312,45.0%) ,then high-dose cytarabine (n=222,32.0%), VR-CAP(n=44,6.3%), BR(n=30,4.3%), R-EPOCH (n = 17, 2.5%), FC / FCM±R regimen (n = 13,1.9%),and 55 patients(7.9%) uesd chemo-free regimen including IR / R2 / IR2 .Only 80 patients (11.5%) received autologous hematopoietic stem cell transplantation as consolidation therapy after chemotherapy remission. The ORR rate was 85.0%with 46.6% CR and 38.4% PR in the initial treatment.During the follow-up to June 2021(2-204months), 222 patients(32.0%) had died. The 5-year PFS and OS was 30.9% and 65.0%respectively.In the multivariate Cox regression model, ki67 ≥ 50% (HR 1.27, 95%CI 1.01-1.60, p = 0.038) ,stageⅢ/Ⅳ (HR1.56, 95%CI 1.05-2.33, p = 0.029),high- intermediate/high risk group accouding to MIPI-c (HR1.56, 95%CI 1.05-2.33, p = 0.008),spleen involvment (HR1.35, 95%CI 1.08-1.69, p = 0.009),without maintenance treatment (HR0.71, 95%CI 0.56-0.88, p = 0.003) ,SD/PD in inital treatment (HR6.20, 95%CI4.71-8.14, p &lt; 0.001) were independently associated with poorer PFS while ki67 ≥50% (HR 1.74, 95%CI 1.31-2.31, p&lt; 0.001),B symtom (HR 1.52, 95%CI 1.15-2.00, p = 0.003), high-intermediate/high risk group accouding to MIPI-c (HR1.43, 95%CI 1.24-1.64, p &lt; 0.001),without high-dose cytarabine (HR0.47, 95%CI 0.31-0.70 ,p &lt; 0.001) ,without maintenance treatment (HR0.40, 95%CI 0.28-0.58,p &lt; 0.001)and relapse/refractory state (HR 4.04, 95%CI 2.21-7.39, p &lt; 0.001) were independently associated with poorer OS.
Conclusions This study describes the characteristics of mantle cell lymphoma in Chinese population with younger onset age and a higher tumor proliferation index. High dose cytarabine treatment and maintenance treatment have shown survival benefits in real-world.Recurrence and refractory is an important factor affecting survival,the strategy of combining molecular biological characteristics with novel strategies may improve outcome in these patients.
Figure 1 Figure 1.

Disclosures
No relevant conflicts of interest to declare.