Study objective: To investigate the prognostic significance of interleukin (IL)-10 serum levels in advanced non-small cell lung cancer (NSCLC) patients.
Design: IL-10 serum levels were measured before chemotherapy, on completion of therapy, and at follow-up by means of a commercially available enzyme-linked immunoassay. The results were then analyzed in comparison with other prognostic variables, and a model predicting overall survival (OS) and time to treatment failure (TTF) was finally generated.
Setting: University hospital.
Patients: Sixty consecutive patients with TNM stage III or IV NSCLC undergoing conventional platinum-based regimens.
Results: Elevated levels of serum IL-10 were found in cancer patients with respect to healthy control subjects (17.7 +/- 4.4 vs 9.2 +/- 1.5 pg/mL, respectively; p < 0.05), with patients with metastatic disease showing significantly higher levels than patients with undisseminated cancer (21.0 +/- 4.2 vs 14.3 +/- 1.2 pg/mL, respectively; p < 0.05). Following completion of treatment, patients were classified as responders if they had achieved either one of the following: complete response, partial response, or stable disease; and nonresponders, in case of progressive disease. Retrospective analysis of basal IL-10 serum levels in these two subgroups showed a significant difference between responders and nonresponders (15.2 +/- 2.2 vs 21.4 +/- 4.2 pg/mL, respectively; p < 0.05). Moreover, a further significant increase in IL-10 serum levels was observed in nonresponders at the end of therapy (21.4 +/- 4.2 vs 26.0 +/- 4.3 pg/mL, prechemotherapy and postchemotherapy, respectively; p < 0.05), whereas values in responders were found to have significantly decreased (15.2 +/- 2.2 vs 14.8 +/- 2.2 pg/mL, prechemotherapy and postchemotherapy, respectively; p < 0.05). Using univariate and multivariate analyses, both OS and TTF were shown to be affected by the mean pathologic levels of IL-10. Stepwise regression analysis identified IL-10 serum level and stage as the prognostic factors related to OS, and IL-10 serum level and performance status as the prognostic factors related to TTF.
Conclusions: In conclusion, this study shows that the measurement of pretreatment IL-10 serum levels is of independent prognostic utility in patients with NSCLC and may be useful for detection of disease progression.