Abstract：
The International Consensus Classification (ICC) and World Health Organization (WHO) proposed significant changes to the diagnostic criteria of myelodysplastic syndromes (MDS) in 2022. The impact of these criteria on hematopathology practice is uncertain. This study aims to evaluate the impact of the 2022 ICC and WHO 5th edition classifications on the diagnosis of cytopenias and MDS. Cases from 2021 performed for primary diagnosis of cytopenia(s)/MDS and their clinical, laboratory, and pathologic findings were reviewed and classified according to the new classification systems. The rate of major changes to the diagnosis was determined and potential pitfalls in the diagnostic approach, laboratory workflow, and clinical communication challenges were investigated. A total of 49 cases were recruited. Major changes to the diagnostic entities were made in 18/49 (37%) cases according to the WHO 5th edition, and 23/49 (47%) cases classified according to the ICC. The difference was accounted for by five cases of MDS-EB2 (revised WHO 4th edition) classified as MDS/AML (major change) in the ICC in contrast to no significant change (MDS-IB2) in the WHO 5th edition. MDS-SLD cases were not subject to major reclassification according to either system. The new molecularly defined categories of CCUS/CHIP, MDS-SF3B1, and MDS with biallelic TP53 mutations were almost identically represented in both systems in our cohort. A case of MDS-MLD was reclassified as CMML by both classification systems. There are few but important differences between the new MDS classification systems. A preimplementation assessment is helpful to identify diagnostic and potential clinical impacts of their adoption.
摘要：
国际共识分类（ICC）和世界卫生组织（WHO）提议在2022年对骨髓增生异常综合征（MDS）的诊断标准进行重大更改。这些标准对血液病理学实践的影响是不确定的。本研究旨在评估2022年ICC和WHO第5版分类对血细胞减少症和MDS诊断的影响。从2021年开始进行的主要诊断为血细胞减少症/MDS的病例及其临床，实验室,根据新的分类系统对病理结果进行审查和分类。确定了诊断的主要变化率，并确定了诊断方法中的潜在陷阱。实验室工作流程，和临床沟通挑战进行了调查。共招募了49个案例。根据世界卫生组织第5版，在18/49（37％）病例中对诊断实体进行了重大更改，和23/49（47%）病例根据ICC分类。差异由ICC中分类为MDS/AML（重大变化）的5例MDS-EB2（WHO第4版修订）解释，而WHO第5版中无重大变化（MDS-IB2）。根据这两种系统，MDS-SLD病例均未进行重大重新分类。CCUS/CHIP的新分子定义类别，在我们的队列中，MDS-SF3B1和具有双等位基因TP53突变的MDS在两个系统中几乎相同。两个分类系统均将MDS-MLD病例重新分类为CMML。新的MDS分类系统之间几乎没有但重要的区别。实施前评估有助于确定其采用的诊断和潜在临床影响。
