[Diagnostic and prognostic value of interleukin-6 in malignant non-Hodgkin's lymphomas]

Sixty six patients with non-Hodgkin's lymphomas (NHL) were studied, interleukin-6 (IL-6) was revealed in the blood sera of 33 patients. IL-6 was revealed more frequently in patients with high-grade malignant (p < 0.05) than in those with low-grade malignancy. The largest group of IL-6 positive patients included NHL patients with diffuse large B-cell lymphoma and angioimmunoblastic lymphoma. The marked relationship was found between the serum IL-6 levels and the stage of disease: the serum IL-6 level was significantly lower in untreated patients with Stages II and III disease than in those with end-stage (IV) NHL. IL-6 significantly decreased upon remission, comparable with its level before the initiation of treatment. Analysing the association of prognosis of disease with the serum IL-6 showed that in the group of patients with good (The SNLG index < 2) and intermediate (2 < SNLG index < by 2.6) prognosis, the concentration of this cytokine was significantly lower than in those with poor prognosis (SNLG index > 2.6). There was a significant decrease of the total survival rates of NHL with serum IL-6 found. Therefore, IL-6 is a good prognostic marker in NHL and associated with the activity of a malignant process. Additionally, the increased serum IL-6 levels correlated with NK activities positively and with serum IL-4 levels negatively.