Clin Lab. 2022 Mar 1;68(3). doi: 10.7754/Clin.Lab.2021.210635.
Plasma cell myeloma is a kind of multifocal proliferation of neoplastic plasma cells in bone marrow. Morphology of myeloma plasma cells varies from mature to immature form, plasmablastic, and pleomorphic cells, with the proportion of plasma cells changing from a slight increase to > 90%. Several morphologic variants of PCM have been reported.
Herein, we present a rare case of PCM with typical morphological features of bone marrow metastatic carcinoma, association with CD138 positivity, and a complex karyotype.
The diagnosis of PCM was made based on a combination of the clinical features, morphology, immunofixation electrophoresis, flow cytometry immunophenotyping, and bone marrow biopsy. Overall, the result was in accord with PCM based on the WHO classification.
The case focuses on the wide morphological variants of PCM and highlights the reason why PCM should be taken as a differential diagnosis when one presents with typical morphological feature and common antigens expression of bone marrow metastatic carcinoma.
浆细胞骨髓瘤是骨髓中恶性浆细胞多灶性增殖的一种疾病。骨髓瘤浆细胞的形态从成熟到不成熟形式、浆母细胞样和多形性细胞不等，浆细胞的比例从轻微增加到>90%不等。已经报道了几种浆细胞骨髓瘤的形态变异型。
在此，我们报告一例罕见的浆细胞骨髓瘤病例，其具有典型的骨髓转移癌形态特征，与 CD138 阳性和复杂核型相关。
基于临床特征、形态学、免疫固定电泳、流式细胞术免疫表型和骨髓活检，诊断为浆细胞骨髓瘤。总体而言，根据世界卫生组织分类，结果符合浆细胞骨髓瘤。
该病例重点关注浆细胞骨髓瘤的广泛形态变异型，并强调了当出现典型形态特征和骨髓转移癌常见抗原表达时，浆细胞骨髓瘤应作为鉴别诊断的原因。
