[Detection of soluble interleukin-2 receptor in the serum of patients with non-Hodgkin's lymphoma].

BACKGROUND

Patients with non-Hodgkin's lymphoma (NHL) have increased serum levels of soluble interleukin-2 receptor (sCD25). In this study the authors investigate: a) the value of sCD25, compared to other serum markers, as tumor marker, and b) the relationship of the sCD25 with the response to therapy and prognosis.

PATIENTS AND METHODS

Serum interleukin-2 receptor (sCD25) levels were measured at diagnosis in 63 patients with NHL (low-grade lymphoma 30 and high-grade lymphoma 33).

RESULTS

High levels of sCD25 were found in these patients compared to a control group (median 1,757 U/ml vs 385 U/ml; p < 0.0001). Significant differences were also found between the high-grade group and the low-grade group, as a whole and within the same Ann Arbor stage. sCD25 showed a correlation coefficient higher than other serum parameters (albumin, LDH, beta 2-microglobulin, uric acid, C-reactive protein) with Ann Arbor stage and with the number of involved lymph nodes or extralymphatic organs. In the high-grade NHL, the median of sCD25 (3,000 U/ml) separates patients with differences in the overall survival (p = 0.0138) and in percentage of complete remisions (p = 0.0079). All the patients with sCD25 < or = 3,000 U/ml reached the remision. The association sCD25 > 3,000 U/ml and albumin < 3.5 g/dl selected to 5 out of 6 patients who failed induction chemotherapy, and only 2 out of 22 who reached the remision.

CONCLUSIONS

The sCD25 is the best serum factor for estimating tumor burden in NHL. sCD25 level isolates or associated with albumin provides prognostic information.