Correlation between Soluble Cytoadhesion Molecules (sVCAM-1 and sICAM-1) with Prognostic Markers of Disease Activity in Chronic B-Lymphocytic Leukemia (B-CLL)

Purpose: To investigate the potential usefulness of sVCAM-1 and sICAM-1 in morphologically and immunophenotypically confirmed B-CLL as prognostic markers in newly diagnosed patients and to guide in selecting a treatment protocol. Patients and Methods: The study included 27 newly diagnosed B-CLL patients, in different stages, according to modified Rai classification. Fifteen age and sex matched healthy volunteers were included as a control group. Diagnosis was made in all cases by examination of Leishman-stained peripheral blood and bone marrow smears and was confirmed by phenotypic analysis that was performed on the “Epics profile II” flow cytometer using fluorescein isothiocyanate and phycoerythrin-labeled monoclonal antibodies. Serum levels of sVCAM-1 and sICAM-1 were measured by the ELISA technique. Eighteen out of the 27 patients with elevated sVCAM-1 level were treated with chlorambucil or cyclophosphamide and prednisone. Follow up of the cases was done by serial estimations of sVCAM1 levels in both treated and untreated patients at 3 monthintervals for one year. Results: Both sVCAM-1 and sICAM-1 were well correlated with clinical staging, i.e. B-CLL patients representing high risk stages had significantly higher (p < 0.001) serum levels of sVCAM-1 and sICAM-1 compared with intermediate risk and low risk patients. However, sVCAM1 was more superior and closely reflected the tumor burden in B-CLL than sICAM-1 as it was strongly correlated with clinical staging, lymphocyte count and β2-microglobulin level. In the treated group, during the follow up period, 12 patients showed progressive decline of sVCAM-1 and 10 of them remained alive for the whole time of follow up, whereas the remaining 6 patients showed, more or less, a stationary level of sVCAM-1 and four of them died from disease complications. In the untreated group, 5 patients who had the highest levels of sVCAM-1 progressed rapidly to more advanced stages of the disease and developed complications. Conclusion: sVCAM-1 is a more sensitive prognostic marker than sICAM-1 as it significantly correlates with tumor burden and serum markers. Moreover, sVCAM-1 measurement is easy, reproducible and accurate and can be used as a laboratory tool for deciding a treatment or no treatment policy for patients in early stages of the disease. This needs to be more confirmed in prospective studies on larger numbers of patients and longer follow-up periods.