Udoh Agnes I, Wagner Celeste, Rawas Faisal, Mallick Jayati, Aakash Fnu
Pathology, University of Texas Medical Branch, Galveston, USA.
Hematopathology, University of Texas Medical Branch, Galveston, USA.
Cureus. 2025 May 3;17(5):e83402. doi: 10.7759/cureus.83402. eCollection 2025 May.
Plasma cell leukemia (PCL) is a rare and aggressive form of plasma cell neoplasm, defined by the presence of 5% or more circulating plasma cells in peripheral blood in patients diagnosed with plasma cell myeloma. The spindle-cell morphology in PCL is an exceptionally rare feature, adding diagnostic complexity. This case involves a 56-year-old female with PCL, showing elongated spindle-shaped plasma cells in the peripheral blood smear. Bone marrow aspirate and core biopsy confirmed the spindle morphology and extensive atypical plasma cell infiltration, with minimal trilineage hematopoiesis. Flow cytometry analysis revealed CD14, CD22, CD27, CD38, CD81, CD138, and cytoplasmic immunoglobulin lambda chain positivity, with absence of CD19, CD20, CD56, CD117, and Kappa light chains. Spindle cell morphology in plasma cell neoplasms is rare and diagnostically challenging. Additionally, CD22 positivity suggests a unique immunophenotypic profile, potentially representing an intermediate stage between immunoblasts and mature plasma cells. This report documents the first case of CD22-positive PCL with spindle cell morphology.
浆细胞白血病（PCL）是一种罕见且侵袭性的浆细胞肿瘤形式，定义为在被诊断为浆细胞骨髓瘤的患者外周血中存在5%或更多的循环浆细胞。PCL中的梭形细胞形态是一种极为罕见的特征，增加了诊断的复杂性。该病例涉及一名56岁的PCL女性患者，其外周血涂片显示有细长的梭形浆细胞。骨髓穿刺和活检证实了梭形形态以及广泛的非典型浆细胞浸润，三系造血极少。流式细胞术分析显示CD14、CD22、CD27、CD38、CD81、CD138和细胞质免疫球蛋白λ链呈阳性，而CD19、CD20、CD56、CD117和κ轻链缺失。浆细胞肿瘤中的梭形细胞形态罕见且诊断具有挑战性。此外，CD22阳性提示一种独特的免疫表型特征，可能代表免疫母细胞和成熟浆细胞之间的中间阶段。本报告记录了首例具有梭形细胞形态的CD22阳性PCL病例。
