Breccia Massimo, Latagliata Roberto, Carmosino Ida, Gentilini Fabiana, D'Elia Gianna Maria, Levi Anna, Natalino Fiammetta, Frustaci Annamaria, De Cuia Maria Rosaria, Alimena Giuliana
Department of Cellular Biotechnology and Hematology, University La Sapienza, Rome, Italy.
Acta Haematol. 2007;117(4):221-5. doi: 10.1159/000098957. Epub 2007 Jan 26.
One of the major changes suggested by the World Health Organization (WHO) classification with respect to the French-American-British (FAB) proposal for myelodysplastic syndromes (MDS) was to lower the bone marrow (BM) blast count from 30 to 20%, thus eliminating the refractory anaemia with excess of blasts in transformation (RAEB-t) category. However, a general consensus has not been reached, and several authors still retain RAEB-t as an MDS sub-entity. We re-evaluated our series of 74 patients classified as RAEB-t according to the FAB criteria by stratifying them into two subsets: patients with at least 5% peripheral blast (PB) cells but with BM blasts <20% (group I) and patients with BM blastosis between 20 and 30% and PBs <5% (group II). We found differences among the two groups regarding sex, haematological parameters at presentation (white blood cell and neutrophil counts, haemoglobin level) and frequency of infectious episodes during the course of disease. We did not find differences as to the frequency of acute myeloid leukaemia transformation, but a significant difference was evidenced as to survival (9.3 vs. 16 months in group I vs. group II, respectively; p = 0.02). Furthermore, at our institution, we compared the RAEB-t group I patients who, based on >5% PBs, should be included in the RAEB-II category according to the WHO criteria, with a group of 98 patients who were diagnosed as RAEB-II according to the WHO criteria. The findings showed that the aggregation of these two subsets appeared inappropriate, because patients of the two groups showed different clinical features and rates of acute transformation. In conclusion, the RAEB-t entity according to the FAB criteria, although including heterogeneous clinical patient subsets, should more likely be considered as an advanced stage of MDS, rather than a true acute myeloid leukaemia.
世界卫生组织（WHO）对法美英（FAB）提出的骨髓增生异常综合征（MDS）分类建议的一项主要变化是，将骨髓原始细胞计数从30%降至20%，从而取消了转化中伴过多原始细胞的难治性贫血（RAEB-t）类别。然而，尚未达成普遍共识，几位作者仍将RAEB-t保留为MDS的一个亚实体。我们根据FAB标准对74例被分类为RAEB-t的患者进行了重新评估，将他们分为两个亚组：外周血原始细胞（PB）至少5%但骨髓原始细胞<20%的患者（第一组）和骨髓原始细胞在20%至30%且外周血原始细胞<5%的患者（第二组）。我们发现两组在性别、就诊时的血液学参数（白细胞和中性粒细胞计数、血红蛋白水平）以及疾病过程中感染发作的频率方面存在差异。我们未发现急性髓系白血病转化频率的差异，但在生存率方面存在显著差异（第一组与第二组分别为9.3个月和16个月；p = 0.02）。此外，在我们机构，我们将基于外周血原始细胞>5%、根据WHO标准应纳入RAEB-II类别的第一组RAEB-t患者与一组根据WHO标准诊断为RAEB-II的98例患者进行了比较。结果表明，将这两个亚组合并似乎不合适，因为两组患者表现出不同的临床特征和急性转化发生率。总之，根据FAB标准的RAEB-t实体，尽管包括异质性的临床患者亚组，但更可能应被视为MDS的晚期阶段，而非真正的急性髓系白血病。
