Soluble CD44 in patients with aggressive non-Hodgkin's lymphoma: Prognostic and clinical value

Abstract

e19539 Background: CD44 is a cell surface glycoprotein expressed by a large variety of tissues. In addition to their expression on the cell membrane, CD44 proteins are also released from cells, and soluble CD44 proteins are detectable in the normal human circulation. The observation that several human tumors show an overexpression of CD44 and the presence of soluble CD44 in the circulation makes CD44 a potential serum marker for tumor detection. In this prospective study, we investigated the prognostic and clinical value of s-CD44 in patients with aggressive non-Hodgkin's lymphomas. Methods: s-CD44 concentration was measured in the sera of 64 patients with aggressive non-Hodgkin's lymphomas treated with standard CHOP by using chemiluminescence-enzyme immunoassay (EIA). Results: Circulating serum CD44 (s-CD44) levels have been found to change in parallel with response to therapy, but little is known about the predictive or prognostic significance of s-CD44. The median pretreatment s-CD44 level was 510 ng/mL(range, 90 to 2,120 ng/mL). Only 10 (31%) of the 32 patients with an International Prognostic Index (IPI) score 0 or 1 had s-CD44 concentration higher than the median level, whereas 11 (52%) of 21 patients with an IPI score ≥2 had a concentration higher than the median before initiation of treatment (P < .0001). Patients with lower than the median s-CD44 achieved more often a complete response to therapy (P = .0002) and had better survival (P = .007) than those with higher s-CD44 levels. However, in a multivariate analysis, only the IPI score had independent prognostic value (P < .001). Conclusions: Our results showed that a high s-CD44 level before treatment is associated with a high IPI score, poor response to treatment, and unfavorable prognosis in aggressive non-Hodgkin's lymphoma. No significant financial relationships to disclose.