套细胞淋巴瘤多形性及母细胞亚型3例OA

Objective:Primary splenic mantle cell lymphoma(MCL)is uncommon.This study aims to investigate the clinicopathological characteristics,diagnostic features,and differential diagnostic considerations of the blastoid and pleomorphic variants of MCL,thereby improving recognition of these 2 rare and aggressive subtypes and reducing the risk of misdiagnosis. Methods:Clinical data and imaging findings were collected and analyzed.Histopathological features of tumor cells were evaluated under light microscopy.Immunohistochemistry and in situ hybridization were performed to assess the expression of relevant biomarkers. Results:The patients ranged in age from 60 to 68 years,2 males and 1 female,consistent with the typical age and gender distribution of MCL.Morphologically,the pleomorphic variant was characterized by large tumor cells with marked pleomorphism,highly irregular nuclei,prominent nucleoli,and frequent mitotic figures,closely resembling diffuse large B-cell lymphoma(DLBCL).In contrast,the 2 blastoid variants consisted of medium-sized,relatively monomorphic tumor cells with finely dispersed chromatin and inconspicuous nucleoli.These tumors exhibited diffuse solid-sheet growth,with focal indistinct nodular structures and hyalinized vessels,resembling lymphoblastic lymphoma(LBL).Immunophenotypic analysis demonstrated expression of B-cell markers,cyclin D1,and SRY-box transcription factor 11(SOX11).However,CD5 expression was absent in the 2 blastoid variants,representing an atypical immunophenotype.The pleomorphic variant was CD5-positive at initial diagnosis but showed only partial positivity at relapse.The Ki-67 proliferation index was significantly elevated in all cases,ranging from 60％to 90％,consistent with the highly proliferative biological behavior of aggressive lymphomas.In the relapsed pleomorphic case,the Ki-67 index increased further compared with that at initial diagnosis. Conclusion:The blastoid and pleomorphic variants of MCL are highly aggressive subtypes with distinctive clinicopathological features.Their clinical manifestations are nonspecific,and their histological morphology may closely mimic other B-cell lymphomas,particularly DLBCL and LBL.In addition,blastoid MCL may exhibit an atypical CD5-negative immunophenotype,making pathological diagnosis particularly challenging.Accurate diagnosis requires comprehensive integration of clinical information,imaging findings,histomorphological characteristics,and immunophenotypic profiles rather than reliance on a single parameter.Cyclin D1 and SOX11 are core diagnostic markers,whereas a high Ki-67 proliferation index serves as an important indicator of poor prognosis.When encountering cases morphologically resembling DLBCL or LBL,pathologists should include blastoid and pleomorphic MCL in the differential diagnosis to reduce misdiagnosis.Such recognition is crucial for prognostic assessment and optimization of patient management.