The time-dependent prognostic value of intratumoral cytokine expression profiles in a natural course of primary breast cancer with a long-term follow-up.

Despite the increasing evidence for the importance of immunity in breast cancer, the contradictory role of inflammation has not been thoroughly researched. In this study, we investigate the prognostic value of intratumoral inflammation as evaluated by cytokine mRNA levels. Intratumoral mRNA was measured for IL1β, IL6, IL8, IL10 and IL17A, using Taqman quantitative PCR. By the AUC criteria, none of the cytokines associated with metastasis outcome over the entire follow-up period. However, separation of the follow-up period has revealed a time-dependent and robust prognostic association of IL β. It discriminated between patients with and without metastasis relapse by AUCs of 0.21 and 0.82 during the early and late follow-up of 0-7 and 7-14 years, respectively. Interestingly, the prognostic effect by IL1β shifted during follow-up from good prognosis in the first seven years to bad prognosis thereafter. By the less stringent criteria of Cox regression analysis, other cytokines also significantly associated positively or negatively with metastasis outcome. IL17A associated with good prognosis in the first 7 years of follow up while IL6 associated with poor and IL10 with good prognosis from 7 to 14 years. The revealed time-dependent prognostic effects of cytokine mRNA levels are intriguing and may reflect valuable biological information which should be considered in breast cancer immunotherapy research.