Prognostic Significance of IL-6 in Hodgkin Lymphoma.

Elevated serum interleukin-6 (IL-6) in Hodgkin lymphoma (HL) is reported to correlate with B symptoms, response rate and survival in adult patients. The authors studied prognostic significance of IL-6 expression by immunohistochemistry on Hodgkin-Reed Sternberg cells and background reactive cells in a retrospective cohort of pediatric HL patients treated with doxorubicin, bleomycin, vinblastine and dacarbazine (ABVD) from January 2009 through December 2013. Of 142 patients, tissue blocks were retrieved in 110 patients. On logistic regression analysis, IL-6 expression on background cells alone was among the factors associated with inferior response rate (OR-9.9, 95%CI-1.2, 78.3; p = 0.03). On multivariate analysis, IL-6 expression on background cells alone had significant impact on 5 y freedom from treatment failure (FFTF) (HR-7.7, 95% CI-1.2, 48.6; p = 0.03). IL-6 expression by immunohistochemistry in the background cells is an independent poor predictor of response and FFTF in pediatric HL. Further prospective studies in children are needed to confirm the current findings and whether IL-6 expression can be used to stratify treatment.