Department of Pathology, Hematopathology Section, the James P. Wilmot Cancer Center, University of Rochester Medical Center, Rochester, NY 14642, USA.
Am J Clin Pathol. 2010 Oct;134(4):648-52. doi: 10.1309/AJCPULO8SLW0RKJL.
Cup-like nuclear invaginations (NIs) in acute myeloid leukemia (AML) blasts have been associated with NPM1 mutations. Precision for enumeration of NI blasts has not been previously studied. Furthermore, the sensitivity and specificity for the morphologic prediction of NPM1 mutations have been variously reported. By using 66 AML specimens (17 with NPM1 mutations and 49 without), we found that interobserver reproducibility for enumeration of NI blasts was high (r = 0.98) and that identification of this feature was teachable (r = 0.96). No NPM1 mutation-negative case had greater than 7% NI blasts. The fraction of NI blasts was highly variable among 17 NPM1 mutation-positive cases, ranging from 0% to greater than 40%. These data indicate that an NI blast fraction of more than 10% is highly specific for NPM1 mutation-positive cases but with a sensitivity of about 30%. Therefore, although NI blasts can be reliably identified in routine smears and although they are a specific marker of NPM1 mutation-positive cases, the majority of NPM1 mutation-positive cases lack this distinctive finding.
杯状核内陷（NIs）在急性髓系白血病（AML）blasts 中与 NPM1 突变有关。以前尚未研究过对 NI blasts 计数的精确性。此外，形态学预测 NPM1 突变的敏感性和特异性也有不同的报道。通过使用 66 例 AML 标本（17 例有 NPM1 突变，49 例无），我们发现，NI blasts 计数的观察者间可重复性很高（r = 0.98），并且可以教授识别这种特征（r = 0.96）。没有 NPM1 突变阴性的病例 NI blasts 比例大于 7%。在 17 例 NPM1 突变阳性病例中，NI blasts 的比例高度可变，范围从 0%到大于 40%。这些数据表明，NI blasts 比例大于 10%对 NPM1 突变阳性病例具有高度特异性，但敏感性约为 30%。因此，尽管 NI blasts 可以在常规涂片上可靠地识别，并且它们是 NPM1 突变阳性病例的特异性标志物，但大多数 NPM1 突变阳性病例缺乏这种明显的发现。
