Clinical Study of Different Doses of Mifepristone in Human Uterine Leiomyoma

Objective:To study the effects of mifepristone on volume,sexual hormones and their receptors in tissues of uterine leiomyoma and clarity the treatment mechanism of mifepristone.Methods:Sixty patients with uterine leiomyoma who had surgical indication but no complication divided into three groups:control group:operate immediately,included 20 cases;short duration-high dose(A) group:treated with mifepristone 100 mg/d for 5 days before operation,included 20 cases;long duration-low dose(B) group:treated with mifepristone 12.5 mg/d for 90 days beginning on the first day of menstrual cycle before operation,also included 20 cases.The volume of leiomyoma was measured by ultrosonography at the time of pre-treated and post-treated.FSH,LH,E,P levels were measured at the time of pre-treated and post-treated.ER,PR levels in leiomyoma were determined by immunochemistry method of IP two step.Results:(1) Compared with that of pre-treatment,the leiomyoma volume decreased in both group A and B.The difference was significant(P0.05).The significant difference of inhibition rate was observed in two treated groups(P0.01).(2) The change of FSH,LH,E,P has no significant difference between pre-treatment and post-treatment in two treated groups.FSH presented descendent tendency,E maintain follicular phase level.(3) High positive expression rate of ER,PR was observed in control group,while decreased expression of ER、PR in group A and B.Compared with the control group,the difference was significant(P0.05).Meanwhile,the difference was not significant between group A and B(P0.05).Conclusion:(1) High-dose and low-dose mifepristone also present the effect of decreasing leiomyoma volume,but better effect in the condition of low-dose administration.(2)Decreased ER and PR expression may be one important mechanism of mifepristone in treating uterine leiomyoma.