CD38 expression correlates with cell mutation status in chronic lymphocytic leukemia according to a study from the Netherlands

06-28-2006

CD38 expression correlates with cell mutation status in chronic lymphocytic leukemia.

"Increased CD38 expression by leukemic cells has been suggested as an adverse prognostic factor in B-CLL. Several approaches have been proposed to quantify its level of expression by flow cytometry," wrote J.G. Boonstra and colleagues, University of Rotterdam.

They continued, "We compared the use of (i) the percentage of CD38 positive cells, (ii) CD38 antibodies bound per cell (ABC), and (iii) a semi-quantitative method based on the shape of the CD38 histogram, within a cohort of 78 B-CLL patients."

"A decreased overall survival was seen with >30% CD38 positivity among B-CLL cells, with CD38 ABC >100, and with bimodal or unimodal, strongly positive CD38 histograms. However, patients with unimodal weakly positive CD38 histograms also showed a significantly reduced survival as did patients with intermediate proportions (i.e. 5-30%) of CD38+ cells.

"Furthermore, within the group with <5% CD38 positivity among their B-CLL cells, 84% of patients showed prognostically favourable mutated IGVH gene segments and 100% had low ZAP70 gene expression. For 5-30% CD38 positivity, these proportions were 50 and 83%, while for >30% CD38 positivity, these proportion were only 28 and 56%, respectively," wrote the researchers.

The scientists concluded, "We found a simple method of quantitation of CD38 expression (i.e., >5% CD38 positivity among B-CLL cells) to be sufficient to identify patients with an unfavourable prognosis. The level of CD38 expression as defined with this method correlated well with the IGVH mutation status and ZAP70 gene expression."

Boonstra and colleagues published the results of their research in Cytometry Part B - Clinical Cytometry (CD38 as a prognostic factor in BCeH chronic lymphocytic leukaemia (B-CLL): Comparison of three approaches to analyze its expression. Cytometry B Clin Cytom, 2006;70B(3):136-141).

For additional information, contact J.G. Boonstra, University of Rotterdam, Medical Center, Department of Clinical Chemistry, Dr. Daniel Den Hoed Cancer Center, POB 5201, NL-3008 AE Rotterdam, Netherlands.

The publisher of the journal Cytometry Part B - Clinical Cytometry can be contacted at: Wiley-Liss, Division John Wiley & Sons Inc., 111 River St., Hoboken, NJ 07030, USA.

Keywords: Rotterdam, Netherlands, CD38, Chronic Lymphocyte Leukemia, Diagnostics, Prognostics, Gene Expression.

This article was prepared by Hematology Week editors from staff and other reports. Copyright 2006, Hematology Week via NewsRx.com.