Clinical significance of serum CD44 measurement in malignant lymphoma.

We monitored the effectiveness of lymphoma therapy by measuring the serum levels of soluble CD44std (sCD44std) and soluble CD44v6 (sCD44v6). Furthermore, we measured the level of soluble interleukin 2 receptor (sIL-2R). A total of 24 patients with non-Hodgkin's lymphoma were enrolled. sCD44std, sCD44v6, and sIL-2R on serum were measured using ELISA system. In all patients, only the sIL-2R level decreased significantly following therapy. However, an analysis of CR and PR showed that the degree of decrease in the sCD44std level was significantly greater than that in the sIL-2R level. Furthermore, among the CS IV cases, only the CD44std level decreased significantly after therapy. These findings suggest that the level of serum sCD44std reflects clinical pathology more closely than the level of serum sIL-2R in CS IV patients and those who respond well to therapy. Moreover, when T-cell and B-cell lymphomas were analyzed separately, the levels of sCD44std and sIL-2R decreased significantly after therapy in patients with B-cell lymphomas, and the degree of decrease in the sCD44std level was very significant with a p-value of 0.0003. This suggests that when sCD44std is used as an index of treatment, it more closely reflects the treatment of B-cell lymphomas. Level of serum sCD44std should prove to be a useful marker for assessing the effectiveness of lymphoma therapy.