Efficacy Observation Of Chidamide Combined With Chemotherapy In Treatment Of Peripheral T Cell Lymphoma And Prognostic Analysis

Background and ObjectivePeripheral T cell lymphoma(PTCL)is a group of hematologic malignant originating from mature T/NK cells,with a high degree of heterogeneity.At present,there is no clear first-line treatment for PTCL,and its’prognosis and efficacy are poor.In recent years,many new drugs have been developed and applied to PTCL,among which the histone deacetylase inhibitor(HDACi)attracted much attention.The purpose of this study was to investigate the efficacy of clinical efficacy of HDACi(Chidamide)combined with chemotherapy in treatment of PTCL and the prognostic factors of PTCL.Methods42 patients diagnosed with PTCL by tissue biopsy and immunohistochemistry in the department of hematology,the first affiliated hospital of Guangzhou medical university from August 2013 to October 2019 were collected,and excluding those patients who are younger than 18 years old or diagnosed with ALK+ALCL.The information collected in the studies included general information(age,gender,tissue pathological diagnosis,tissue immunohistochemistry,Ann Arbor stage,performance status,prognostic index for T-cell lymphoma score,tumor size,extranodal involvement,treatment response,overall survival,progression-free survival),treatment(whether or not to use Chidamide,radiation therapy and hematopoietic stem cell transplantation)and laboratory data(blood routine,serumβ2-microglobulin,serum biochemical indicators,EBV DNA,HBV-DNA).All datas were analyzed by SPSS16.0:Quantitative data between two groupswere statistically analyzed by T test or rank sum test,while qualitative data were statistically analyzed by chi-square test or Fisher exact probability method.Kaplan-meier method was used for survival analysis,and log-rank test was used to analyze the univariate correlation between overall survival(OS)and progression-free survival(PFS).Multivariate analysis was used to analyze the independent correlation between PFS and OS through Cox regression model.P<0.05 was defined as statistically significant,and all tests were bilateral.Results1.Clinical efficacy of Chidamide combined with chemotherapy in treatment of primary peripheral T cell lymphoma.The CR rate and ORR were 50.0%and 69.2%respectively in 26 patients with initial PTCL treated with Chidamide combined with chemotherapy,while the CR rate and ORR were 31.3%and 62.5%respectively in 16 patients with initial PTCL treated with conventional chemotherapy.The CR rate of Chidamide group was significantly higher than the conventional chemotherapy group,but there was no difference between the two groups(CR:P=0.233;ORR:P=0.653);The median PFS time of initially diagnosed PTCL patients treated with Chidamide combined chemotherapy and conventional chemotherapy were 11.5 months vs10.0 months.The 1-year PFS rate,1-year OS rate and 2-year OS rate were 47%,67%,and 53%respectively in patients with initial PTCL treated with Chidamide combined with chemotherapy,while 1-year PFS rate,1-year OS rate and2-year OS rate rate were 25%,44%,and 35%respectively in patients with initial PTCL treated with conventional chemotherapy.The PFS and OS time of the Chidamide combined chemotherapy group was better than the conventional chemotherapy group,but there was no statistical difference in PFS and OS between the two groups(PFS:P=0.72;OS:P=0.36).In the Chidamide combined chemotherapy group,the ORR of CD56-positive patients was 0.0%and that of CD56-negative patients was 87.5%,showing differences(P=0.024),while there was no difference in the expression of other immunophenotypes(including CD2,CD5,CD20 and EBER).The common adverse reactions in the Chidamide combined with chemotherapy group and the conventional chemotherapy group included myelosuppression,fatigue,vomiting and pulmonary infection,and incidence of grade III/IV granulocytopenia,anemia,and thrombocytopenia were 53.8%vs.62.5%,61.5%vs.75.0%,and 57.7%vs.68.8%,respectively,but there was no significant difference between two groups.2.Prognostic factor analysis of peripheral T-cell lymphoma.In univariate analysis,PS score>1(P=0.001),high serumβ2-microglobulin count(β2-microglobulin>3 mg/L)(P=0.016)and low platelet count(platelet<100 x10~9/L)(P=0.001)and hypoalbuminemia(serum albumin<35 g/L)(P=0.022)are the poor-prognostic factors for PFS,while CR after first-line treatment(within six sessions)(P=0.001)is the good-prognostic factors for PFS.PS score>1(P=0.001),B symptoms(P=0.013),IPI score>2(P=0.028),high serumβ2-microglobulin count(P=0.012),low platelet count(P=0.001),hypoalbuminemia(P=0.009)and prognostic index for T-cell lymphoma(PIT)score>1(P=0.016)are the poor-prognostic factors for OS,while CR after first-line treatment(P=0.001)is a good-prognostic factor for OS.In multivariate analysis,low platelet count is an independent poor-prognostic factor for PFS(RR=3.601,95%CI 1.353-9.583;P=0.010),while CR after first-line treatment is an independent good-prognostic factor for PFS(RR=0.187,95%CI 0.075-0.467;P=0.001).Low platelet countis the independent poor-prognostic factors for OS(RR=2.838,95%CI1.101-7.319;P=0.031),while CR after first-line treatment is an independent good-prognostic factor for OS(RR=0.198,95%CI 0.055-0.718;P=0.014).Conclusion1.Chidamide combined with chemotherapy had a high rate of complete response in the initial treatment of PTCL patients.2.PTCL patients with CD56-negative suggests good prognosis.3.Chidamide combined with chemotherapy was safe in the initial treatment of PTCL patients.4.PTCL patients who achieved complete remission after first-line treatment had better PFS and OS.5.Low platelet count at initial onset of PTCL patients suggests poor prognosis.