A diagnosis of typical chronic lymphocytic leukemia (CLL) requires the presence of ≥5000 clonal B-lymphocytes/μL, the coexistence of CD19, CD20, CD5, and CD23, the restriction of light chain immunoglobulin, and the lack of expression of antigens CD22 and CD79b. Atypical CLL (aCLL) can be distinguished from typical CLL morphologically and immunophenotypically. Morphologically atypical CLL cells have been defined mainly as large, atypical forms, prolymphocytes, or cleaved cells. However, current aCLL diagnostics rely more on immunophenotypic characteristics rather than atypical morphology. Immunophenotypically, atypical CLL differs from classic CLL in the lack of expression of one or fewer surface antigens, most commonly CD5 and CD23, and the patient does not meet the criteria for a diagnosis of any other B-cell lymphoid malignancy. Morphologically atypical CLL has more aggressive clinical behavior and worse prognosis than classic CLL. Patients with aCLL are more likely to display markers associated with poor prognosis, including trisomy 12, unmutatedIGVH, and CD38 expression, compared with classic CLL. However, no standard or commonly accepted criteria exist for differentiating aCLL from classic CLL and the clinical significance of aCLL is still under debate. This review summarizes the current state of knowledge on the morphological, immunophenotypic, and genetic abnormalities of aCLL.
典型慢性淋巴细胞白血病（CLL）的诊断需满足以下条件：克隆性B淋巴细胞计数≥5000/μL，同时表达CD19、CD20、CD5和CD23抗原，呈现免疫球蛋白轻链限制性，且不表达CD22与CD79b抗原。非典型CLL（aCLL）可通过形态学与免疫表型特征与典型CLL相区分。形态学上，非典型CLL细胞主要表现为大型异型细胞、幼淋巴细胞或裂细胞。然而，当前aCLL的诊断更侧重于免疫表型特征而非形态学异型性。免疫表型方面，非典型CLL与经典CLL的区别在于缺失一种或更少表面抗原（最常见为CD5和CD23），且患者不符合其他B细胞淋巴系统恶性肿瘤的诊断标准。形态学非典型CLL较经典CLL具有更强的侵袭性临床行为和更差的预后。与经典CLL相比，aCLL患者更易出现预后不良相关标志物，包括12号染色体三体、免疫球蛋白重链可变区未突变状态以及CD38表达。然而，目前尚缺乏区分aCLL与经典CLL的标准或公认标准，且aCLL的临床意义仍存在争议。本综述总结了当前关于aCLL形态学、免疫表型及遗传学异常的研究进展。
肿瘤(癌症)患者之家