MEDROXYPROGESTERONE ACETATE TREATMENT REDUCES SERUM INTERLEUKIN-6 LEVELS IN PATIENTS WITH METASTATIC BREAST-CARCINOMA

BACKGROUND. The serum interleukin (IL)-6 concentration was very low in patients with metastatic breast carcinoma who had received oral medro xyprogesterone acetate (MPA) treatment as compared with those who had not. Accordingly, the authors conducted a prospective study to determi ne whether MPA treatment reduces the serum level of IL-6 in patients w ith this disease. METHODS, In 21 consecutive Japanese patients who wer e scheduled to receive oral MPR treatment at doses of 600, 800 or 1200 mg/day, serum concentrations of IL-6 were determined with a sensitive enzyme-immunoassay prior to the administration of MPA and again at 4 weeks after the treatment was started. In addition, plasma levels of M PA were determined by high-performance liquid chromatography (HPLC). R ESULTS, For weeks after the oral MPA therapy was started, serum IL-6 l evels decreased in all 21 patients regardless of whether or not they r esponded to the treatment. Although the extent of decrease in the seru m IL-6 (Delta IL-6) did not correlate with the daily dose of MPA, it c orrelated closely with the plasma MPA level in these patients. Subject ive improvement in appetite and weight gain were more frequent in the Delta IL-6 > 3 pg/mL group compared with the Delta IL-6 less than or e qual to 3 pg/mL group (80% vs. 45% and 70% vs. 45%, respectively). Sim ilar results were obtained for improvement in patients' sense of well- being (100% vs. 55%). CONCLUSIONS. Oral MPA treatment reduces serum IL -6 concentration in patients with metastatic breast carcinoma, but the decrease is not associated with response to MPA. This observation mar indicate a potential of this agent for producing subjective improveme nt. (C) 1996 American Cancer Society.