CD38 as a prognostic marker in CLL.

Cell-surface expression of CD38 in CLL has been recognised recently as a marker of progressive disease and poor outcome. In contrast to traditional staging systems, CD38 is able to identify progressive cases at an early stage. Measurement of CD38, in conjunction with other novel prognostic factors such as p53 and ZAP-70 helps to identify patients who might benefit from early and more intensive therapy. In addition, CD38 positivity can predict unmutated IgVH gene mutation status in most cases. These features, together with its easy applicability, render CD38 a valuable tool in the routine diagnostics of CLL. Questions remaining to be clarified about CD38 include the incidence and significance of its variations during the course of the disease, the optimal method to define CD38 positivity and the impact of different methodologies on results. Only after these issues are resolved can the definitive place of CD38 be defined in the diagnostics of CLL.