Clinicopathological And Prognostic Features Of Diffuse Large B-cell Lymphoma With HBV Infection

ObjectiveDiffuse large B cell lymphoma(DLBCL)is the most common form of non-Hodgkin lymphoma(NHL).The infection rate of hepatitis B virus(HBV)among DLBCL patients is higher than that of the general population and other tumor patients,and some studies have confirmed that the occurrence and development of DLBCL is related to HBV infection.China is a high incidence region of HBV infection,but there are few reports on the clinicopathological and prognostic features of patients with HBV infection and DLBCL.The purpose of this study was to investigate the clinicopathological features and prognostic factors of DLBCL with HBV infection patients.Materials and Methods(1)Patients and tissue collection: A retrospective analysis was performed on 420 initially treated DLBCL NOS patients with two and a half test records of hepatitis B admitted to Fujian cancer Hospital from March 2011 to February 2018,and complete clinical,laboratory,and follow-up data were collected.The follow-up was up to January 2019.The overall survival was determined from the date of diagnosis to the date of death or the last follow-up.All patients received standard CHOP(cyclophosphamide,doxorubicin,vincristine and prednisone)regimens or rituximab plus CHOP(R-CHOP)as the first-line treatment.HBs Ag-positive patients routinely received lamivudine or entecavir prophylactic treatment,starting from the beginning of chemotherapy and stopping one year after its completion.(2)Histology and immunohistochemical analysis: Biopsy specimens were fixed in 10%formalin and embedded in paraffin after routine histological tissue processing.Three to four micrometer-thick formalin-fixed paraffin-embedded tissue(FFPE)sections were stained with hematoxylin-eosin(HE)for microscopic examination.All immunohistochemistry assays were performed on diagnosed patient tissues available in the form of FFPE tissue blocks using two steps of immunohistochemistry envision for CD20,CD21,CD3,Ki-67,CD10,BCL6,IRF4/MUM1,CD5,CD30,Cyclin D1,BCL2,MYC,P53 and PD-L1.(3)In situ hybridization: Epstein-Barr virus(EBV)detection by in situ hybridization was performed in all cases using FITC-labeled oligonucleotide probe supplied by Ventana to detect EBV-encoded RNA(EBER).In situ hybridization for EBER was conducted on FFPE sections on an automated stainer(Ventana-Benchmark XT)according to the manufacturer’s instructions.(4)Fluorescence in situ hybridization: MYC,BCL2 and BCL6 gene fracture probes were used to detect the rearrangement of MYC,BCL2 and BCL6 genes in patients with high expression of MYC protein and observed under fluorescence microscope.(5)Statistical analysis: SPSS22.0 and Graph Pad Prism software were used for statistical processing.The patient’s characteristics were compared across different subgroups using Pearson’s chi-squared test or Fisher’s exact test.Univariate analysis and survival curves were generated by the Kaplan–Meier method and compared using the log-rank test.Multivariate analysis was conducted with the Cox proportional hazards model,which included the variables that were significant in the univariate analysis.A P-value of <0.05 was considered statistically significant.Results(1)Baseline clinical characteristics of all DLBCL patients: 420 cases of DLBCL included 237 males and 183 females,with a male to female ratio of 1.3: 1.The age of onset was 16 to 86 years,the median age was 53 years,and the average age was 51.6years.Ann Arbor staging: 66 patients(15.7%)in stage I,150 patients(35.7%)in stage II,78 patients(18.6%)in stage III,and 126 patients(30.0%)in stage IV.Patients with low international prognosis index(IPI)(1~2)and high IPI(3~5)were 335(79.8%)and 85(20.2%),respectively.Symptoms of B,mass ≥7.5cm,increased lactate dehydrogenase(LDH),extranodal involvement ≥2 were were identified in 43(10.2%),74(17.6%),194(46.2%),and 71(16.9%)patients,respectively.The follow-up time ranged from 58.0 to65.8 months.The 3-and 5-year OS rates were 71.3% and 64.9%,respectively.One hundred and forty-four of the 420 patients died of the disease.(2)HBV prevalence in DLBCL patients: Among the 420 DLBCL patients,127 were HBs Ag+DLBCL patients(127/420,30.2%),293 were HBs Ag-DLBCL patients(69.8%),and HBV prevalence in DLBCL patients was approximately 30.2%.(3)Clinicopathological features of HBs Ag-positive DLBCL patients: Compared with patients in the HBs Ag-negative group,patients in the HBs Ag-positive group were of a younger age with a median onset age of 50 years(range,18–82)vs 54 years(range,16–86)in the HBs Ag-negative group(P=0.002).HBs Ag-positive DLBCL displayed fewer patients over 60 years(17.3% vs.33.1%,P<0.001),more frequent involvement of the spleen(19.7% vs.6.1%,P<0.001),less frequent involvement of the small and large intestine(2.3% vs 11.2%,P=0.003),more advanced disease(stage III~IV: 56.7% vs.45.1%,P=0.028),and lower expression rate of MYC(49.1% vs.66.7%,P=0.026).There was no significant difference in sex,bulky mass,performance status,B symptoms,elevated LDH,extra-nodal sites ≥2,high IPI,use of rituximab,response to primary chemotherapy,cell of origin,Ki-67 proliferation index,expression of BCL2,P53,PD-L1 expression,and coexpression of BCL2 and MYC between the HBs Ag-positive and-negative groups.(4)Univariate and multivariate survival analysis: Patients in the HBs Ag-positive group did not show significantly worse OS than those in the HBs Ag-negative group with a3-year OS of 73.6% vs 70.2% and a 5-year OS of 63.0% vs 65.6%(P=0.577).Univariate survival analysis showed that in the HBs Ag-positive DLBCL subgroup,age older than60 years,advanced disease,elevated lactate dehydrogenase(LDH),spleen involvement,B symptoms,and double expressers of MYC and BCL2 had a significantly worse outcome,and patients treated with R-CHOP(rituximab plus cyclophosphamide,doxorubicin,vincristine,and prednisone)had a better prognosis.However,sex,bulky mass,performance status,extra-nodal sites≥2,HBV DNA load,HBe Ag,cell of origin,high expression of Ki-67 proliferation index,BCL2,MYC,PD-L1 and P53 did not affect prognosis(All P values were > 0.5).Multivariate analysis further confirmed that spleen involvement and rituximab use were independent prognostic factors in HBs Ag-positive DLBCL patients.(All P values were<0.05).Conclusions(1)In our study,HBV prevalence in DLBCL patients was approximately 30.2%,which was significantly higher than that of in the general population.(2)HBs Ag-positive DLBCL has unique clinicopathological features and poor prognostic factors.(3)HBV infection did not appear to affect the prognosis of DLBCL patients.(4)The use of rituximab significantly improved OS in HBs Ag-positive DLBCL patients.