CHANGES OF CYTOKINES AND THYROID-FUNCTION IN PATIENTS WITH RECURRENT BREAST-CANCER

The hypothyroid state or nonthyroidal illness is often observed in pat ients with recurrent cancer. High levels of cytokines are frequently o bserved in critically ill patients. Recent studies have shown that int erleukin (IL)-6 may be a cause of nonthyroidal illness. We reported th e relationship between thyroid function and the prognosis of the patie nts with recurrent breast cancer. In this study, we measured the serum level of cytokines (IL-2, IL-6, IL-8) and thyroid function (free T3, free T4, and thyrotropin (TSH)) in 38 patients with recurrent breast c ancer. All patients had recieved three or more different courses of th erapy before they were entered the study. The patients were divided in to three groups according to their response to therapy. There were 16 partial response (PR), 10 no change (NC) and 11 progressive disease (P D) patients. They did not receive any medication that influenced the t hyroid hormone level other than medication for cancer. The IL-2 level was under the detectable limit in all groups. No abnormal levels of cy tokines were observed in the PR group. IL-6 and IL-8 levels in the PD group were significantly higher than that in the NC group (p<0.05). Si gnificant negative correlation was observed between IL-6 and thyroid h ormones (free T3, free T4). Patients whose IL-6 level was 20 pg/ml or more died within four months after the beginning of the treatment. We concluded that IL-6 may lead to a hypothyroid state in patients with r ecurrent breast cancer. A high level of IL-6 and IL-8 means the confus ion of the defense system in hosts. Therefore, these cytokines will be predictive indicators of the therapeutic response and the prognosis o f the patients with recurrent breast cancer.