Elevated serum CD44 level is associated with unfavorable outcome in non-Hodgkin's lymphoma

CD44 molecule is a cell surface glycoprotein involved in many cell-cell and cell-matrix interactions. 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. In the present study, we measured s-CD44 levels in sera taken before treatment from 194 patients with non-Hodgkin's lymphoma using a chemiluminescence-enzyme immunoassay method. All except 1 patient were regularly followed-up after therapy at least for 60 months (range, 33 to 143 months). The median pretreatment s-CD44 level was 440 ng/mL (range, 13 to 1,220 ng/mL). Only 32% of the 92 patients with an International Prognostic Index (IPI) score of 0 or 1 had an s-CD44 concentration higher than the median as compared with 67% of the patients with an IPI score >/=2 (P < .0001). Patients with lower than the median s-CD44 achieved more often a complete remission 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). The findings were similar if only the patients with diffuse large-cell lymphoma (n = 51) were included in the analysis, but among patients with low-grade lymphoma, the median s-CD44 level was not significantly associated with the IPI or survival. In conclusion, a high s-CD44 level at diagnosis is associated with a high IPI score, poor response to treatment, and unfavorable outcome in non-Hodgkin's lymphoma.