Computerized texture analysis of atypical immature myeloid precursors in patients with myelodysplastic syndromes: an entity between blasts and promyelocytes

<p>Abstract</p> <p>Background</p> <p>Bone marrow (BM) blast count is an essential parameter for classification and prognosis of myelodysplastic syndromes (MDS). However, a high degree of cell atypias in bone marrow hemopoietic cells may be found in this group of clonal disorders, making it difficult to quantify precisely myeloblasts, and to distinguish them from promyelocytes and atypical immature myeloid precursors. Our aim was to investigate whether computerized image analysis of routine cytology would help to characterize these cells.</p> <p>Methods</p> <p>In May-Grünwald-Giemsa stained BM smears of 30 newly diagnosed MDS patients and 19 cases of normal BM, nuclei of blasts and promyelocytes were digitalized and interactively segmented. The morphological classification of the cells was done by consensus of two observers. Immature granulocytic precursors, which could not be clearly classified either as blasts or promyelocytes, were called "atypic myeloid precursors". Nuclear morphometry and texture features derived from the co-occurrence matrix and fractal dimension (FD) were calculated.</p> <p>Results</p> <p>In normal BM, when compared to myeloblasts, nuclei of promyelocytes showed significant increase in perimeter and local texture homogeneity and a decrease in form factor, chromatin gray levels, Haralick's entropy, inertia, energy, contrast, diagonal moment, cluster prominence, the fractal dimension according to Minkowski and its goodness-of-fit. Compared to normal myeloblast nuclei, the chromatin texture of MDS myeloblasts revealed higher local homogeneity and goodness-of-fit of the FD, but lower values of entropy, contrast, diagonal moment, and fractal dimension. The same differences were found between nuclei of normal promyelocytes and those of MDS. Nuclei of atypical myeloid precursors showed intermediate characteristics between those of blasts and promyelocytes according to the quantitative features (perimeter, form factor, gray level and its standard deviation), but were similar to promyelocytes according to the texture variables inertia, energy, contrast, diagonal moment, cluster prominence, and Minkowski's fractal dimension.</p> <p>Conclusion</p> <p>BM atypical immature myeloid precursors are difficult to be correctly classified in routine cytology. Although their cytoplasm is more similar to that of myeloblasts, computerized texture analysis indicates a nuclear chromatin remodeling more close to the promyelocyte, thus indicating an asynchronous intermediate maturation stage between blast and promyelocyte.</p

Flow cytometry "Ogata score" for the diagnosis of myelodysplastic syndromes in a real-life setting : a Latin American experience

Flow cytometry (FC) is a helpful tool for the diagnosis of myelodysplastic syndrome (MDS). Different FC score systems have been developed. The "Ogata score" is a simple diagnostic score that has been validated having a sensitivity of 69% and a specificity of 92% in low-risk MDS. We aimed to study the feasibility and the utility of the "Ogata score" for the diagnosis of MDS among Latin America (LA) Laboratories. Methods This is a case and control study conducted in LA institutions members of Grupo Latinoamericano de Mielodisplasia (GLAM). A total of 146 MDS patients and 57 control patients were included. "Ogata score" was calculated. Results The sensitivity of "Ogata score" was 75.6% (95% CI, 66.8-81.3), specificity was 91.2% (95% CI, 79.7-96.7), PPV was 95.6% (95% CI, 88.5-98.3), and NPV was 65.4% (95% CI, 49.1-71.9). In low/intermediate-1 IPSS patients group, the sensitivity was 70.1% (95% CI, 60.2-78.2), specificity was 91.2% (CI-95%, 79.7-96.7), PPV was 94.2% (95% CI, 86.4-97.8), and NPV was 62.1% (95% CI, 53.0-78.7). In the group of patients "without MDS specific markers" (patients without ring sideroblasts, blast excess, or chromosomal abnormalities), the sensitivity was 66.7% (CI-95%, 55.8-76.0), specificity was 91.2% (95% CI, 79.7-96.7), PPV was 92.3% (95% CI, 82.2-97.1), and NPV was 63.5% (95% CI, 51.9-73.5). The diagnostic power found in this study was similar to the reported by Della-Porta et al. Also in LA, the analysis was made in modern equipment with acquisition of at least 100 000 events which permits a good reproducibility of the results41453654