CD34/QBEND10 immunostaining in bone marrow biopsies: an additional parameterfor the diagnosis and classification of myelodysplastic syndromes

Abstract

CD34/QBEND10 immunostaining has been assessed in 150 bone marrow biopsies (BMB) including 91 myelodysplastic syndromes (MDS), 16 MDS-related AML, 25 reactive BMB, and 18 cases where RA could neither be established nor ruled out. All cases were reviewed and classified according to the clinical and morphological FAB criteria. The percentage of CD34-positive (CD34 +) hematopoietic cells and the number of clusters of CD34+ cells in 10 HPF were determined. In most cases the CD34+ cell count was similar to the blast percentage determined morphologically. In RA, however, not only typical blasts but also less immature hemopoietic cells lying morphologically between blasts and promyelocytes were stained with CD34. The CD34+ cell count and cluster values were significantly higher in RA than in BMB with reactive changes (p<0.0001 for both), in RAEB than in RA (p=0.0006 and p=0.0189, respectively), in RAEBt than in RAEB (p=0.0001 and p=0.0038), and in MDS-AML than in RAEBt (p<0.0001 and p=0.0007). Presence of CD34+ cell clusters in RA correlated with increased risk of progression of the disease. We conclude that CD34 immunostaining in BMB is a useful tool for distinguishing RA from other anemias, assessing blast percentage in MDS cases, classifying them according to FAB, and following their evolution.

Immunophenotypic clustering of myelodysplastic syndromes

“…Because levels of CD34 normally expressed on CD45 lo control blast cells were within the range of those noted in the CD34 lo /CD38 ϩ branch of MDS patients, CD34 expression could be significant as a prognosis marker rather than as a diagnosis marker of MDS, being probably related to the immaturity level of CD45 lo blast cells. 17,18 By contrast, high levels of CD36 on CD45 lo blast cells of MDS patients may contribute to better defining such patients because (1) it was not found in controls, (2) it was associated with a subset of MDS patients with a majority of RAEB/RAEB-T, but also CMMLs, and (3) it was associated with a poor IPSS score and an increased cytogenetic risk factor without an increase in CD34 expression.…”

Bone marrow trephine findings in acute myeloid leukaemia with multilineage dysplasia

“…This is best evaluated with CD34 and, in cases where leukaemic blasts are CD34 negative, with CD117 or HLA-DR. Quantification in this manner helps us to conform to the criteria required for diagnosing AML as per the WHO classification. The importance of CD34 has been previously explored in the classification and diagnosis of MDS (Baur et al, 2000;Soligo et al, 1994;Torlakovic et al, 2002). In comparison with flow cytometry, BMTB represents marrow in its entirety, whereas aspirated marrow often under-represents the paratrabecular areas.…”

Histopathology in the Diagnosis and Classification of Acute Myeloid Leukemia, Myelodysplastic Syndromes, and Myelodysplastic/Myeloproliferative Diseases

“…7 b) [18,19] . Both an increase in the percentage of CD34-positive cells and a tendency of positive cells to form aggregates have been shown to be reliable predictors of acute leukemic transformation and of poor survival in MDS cases, irrespective of their subtype [13,19,20] . This approach can be used to identify patients with MDS undergoing transition to AML, who are therefore candidates for early aggressive therapy.…”