Objective: To analyze the diagnostic and prognostic values of flow cytometry (FC) in diffuse large B cell lymphoma (DLBCL) with bone marrow involvement (BMI). Methods: The clinical data of 412 patients with newly diagnosed DLBCL, including 243 males and 169 females, aged 64 (28-92) years old, in the Department of Hematology at Peking University Third Hospital from December 2012 to June 2022 were retrospectively analyzed. All patients underwent bone marrow biopsy (BMB) and bone marrow FC. The patients with BMI by FC were further detected by fluorescence in situ hybridization (FISH) for gene analysis. The positive rates and consistency of BMI detected by BMB and FC were evaluated. According to the results of BMB and FC examinations, all patients were divided into four groups: the BMB+FC+group (115 cases), the BMB-FC+group (50 cases), the BMB+FC-group (8 cases, the results did not include in statistical analysis because of small sample size), and the BMB-FC-group (239 cases). The clinical features, treatment response rates, 5-year survival rates, and immunophenotype characteristics by FC in different groups were analyzed. Results: Among the 412 patients with DLBCL, the positivity rates of BMB and FC for BMI detection were 29.9% (123/412) and 40.0% (165/412), respectively. Good consistency between BMB and FC was found (Kappa=0.841, P=0.001). The numbers of extranodal involvement≥2, splenomegaly, huge mass, higher Ki-67 score, higher international prognostic index (IPI) score, thrombocytopenia, and elevated lactate dehydrogenase level were more prevalent in the BMB+FC+group than those in the BMB-FC+group and the BMB-FC-group (all P<0.05). The treatment response rate in BMB+FC+group was 63.5% (73/115), which was lower than those in BMB-FC+group (88.0%, 44/50, P=0.048) and BMB-FC-group (90.0%, 215/239, P=0.032), respectively. The 5-year overall survival rates in three groups were (53.6±9.7) %, (72.5±8.6) %, and (75.2±7.6) %, respectively, with a statistically significant difference (P=0.037). According to the FISH results of bone marrow, 102 cases were diagnosed as not otherwise specified (NOS), 48 cases were diagnosed as double hit lymphoma (DHL), and 15 cases were diagnosed as triple hit lymphoma (THL). Compared with NOS subtypes, the tumor cells in DHL or THL subtypes had higher proportion of increased side scatter (SSC), higher positive rates of CD10 expression, CD38 strong expression and CD56 expression, and lower proportion of surface immunoglobulin light chain restriction (all P<0.05). Conclusions: FC is well consistent with BMB in diagnosing DLBCL with BMI. Combined with FISH detection, FC can contribute to the auxiliary diagnosis and risk stratification for DHL and THL, and provide reference for the prognostic evaluation in DLBCL with BMI.
目的： 探讨流式细胞术（FC）在弥漫大B细胞淋巴瘤（DLBCL）骨髓侵犯诊断和预后评估中的价值。 方法： 回顾性分析2012年12月至2022年6月北京大学第三医院血液科412例初治DLBCL患者的临床资料，其中男243例，女169例，年龄64（28~92）岁。所有患者均进行骨髓活检（BMB）及FC检测，采用荧光原位杂交（FISH）对FC检出骨髓侵犯的患者进行基因分析。评估BMB及FC检出骨髓侵犯的阳性率以及一致性。根据BMB和FC检查结果将患者分为4组：（1）BMB+FC+：115例；（2）BMB-FC+：50例；（3）BMB+FC-：8例（样本量较小，结果未纳入统计分析）；（4）BMB-FC-：239例。分析不同组别DLBCL骨髓侵犯患者的临床特征、治疗有效率、5年生存率以及流式免疫表型特点。 结果： BMB及FC检测骨髓侵犯的阳性率分别为29.9%（123/412）及40.0%（165/412），具有良好的一致性（Kappa=0.841，P=0.001）。BMB+FC+组结外受累数量多（≥2个）、脾肿大、巨大包块、较高增殖指数（Ki-67>70%）、国际预后指数（IPI）高危评分（3~5分）、血小板减少、乳酸脱氢酶升高等临床特征均高于BMB-FC+组和BMB-FC-组（均P<0.05）。BMB+FC+组患者的治疗有效率为63.5%（73/115），低于BMB-FC+组和BMB-FC-组的88.0%（44/50，P=0.048）和90.0%（215/239，P=0.032）。3组患者5年生存率分别为（53.6±9.7）%、（72.5±8.6）%及（75.2±7.6）%，差异有统计学意义（P=0.037）。FISH基因检测结果显示，102例为非特指型（NOS），48例为双打击淋巴瘤（DHL），15例为三打击淋巴瘤（THL）。与NOS亚型相比，DHL、THL亚型肿瘤细胞侧向散射光（SSC）增大的比例更高，CD10表达、CD38强表达及CD56表达阳性率更高，表达胞膜免疫球蛋白限制性轻链比例更低（均P<0.05）。 结论： FC用于诊断DLBCL骨髓侵犯与BMB具有较好的一致性。结合FISH检测，有助于DHL、THL辅助诊断和危险分层，对预后评估具有指导意义。.