BCL2-negative follicular lymphoma:a clinicopathological and molecular genetic analysis of seven cases

SUI Wenwen; LI Jia; ZHONG Xiuming; PAN Yu; WANG Ruihan; LV Beibei

doi:10.3969/j.issn.1007-8096.2026.01.015

Abstract：Objective To explore the clinical and pathological characteristics,immunophenotypes,and molecular genetics of BCL2-negative follicular lymphoma(FL).Methods A retrospective analysis was conducted on the clinical data of 7 cases of BCL2-negative FL to analyze their histopathological characteristics,immunophenotypes,molecular genetic features,and prognosis.Results The patients included 5 males and 2 females,with an age range of 36 to 72 years,and a median age of 51 years.Microscopically,lymph node structures were destroyed,with numerous tumor follicles visible within,loss of follicular polarity,reduction or disappearance of the surrounding mantle zone,absence of the anechoic area,and tumor follicles composed of central cells and centroblastic cells.All tumor cells expressed B-cell markers and germinal center markers BCL6;2 cases showed loss of CD10 expression,all BCL2 were negative,all CD38 were negative or weakly positive,and some CD23 and MUM1 were partially positive(3/7).FISH was performed in 5 cases,and the results showed that 1 case had BCL2(18q21)gene translocation(1/5),and 1 case had BCL2 and BCL6 gene copy number amplification.Clonal IgH and IgK gene rearrangements were tested on 4 biopsy specimens,with 3 cases showing monoclonal configuration(3/4).2 cases underwent simple tumor resection,5 cases received 6-8 cycles of G/R+chemotherapy,followed by G/R consolidation therapy.Follow-up ranged from 12 to 74 months,and currently,all 7 patients were alive.Conclusion BCL2-negative FL is a rare B-cell lymphoma with unique clinical,pathological,and molecular genetic characteristics.It should be differentiated from reactive follicular hyperplasia and childhood follicular lymphoma to improve its understanding and to avoid missed diagnosis,misdiagnosis,and overtreatment.