Efficacy of Use of Long-Term, Low-Dose Mifepristone for the Treatment of Fibroids.

Abstract

Fibroid or myoma is the commonest reported tumor of uterus, and is one of the important reasons for hysterectomy in our setting. Different drugs are available for medical management of fibroid uterus including mifepristone, a progesterone antagonist. Varying dosage regimen for mifepristone was studied as medical management of fibroid uterus. The aim of the project was to study the effect of mifepristone on the symptoms and size of fibroids, especially using a low-dose regimen for 6months. In addition, any symptomatic improvement of menorrhagia and dysmenorrhea was also studied. The study was designed as an observational prospective "before-after" study. Women diagnosed with uterine fibroids attending OPD of a tertiary care hospital were selected according to the inclusion criteria. A total of 36 patients were enrolled in the study. Sample size was calculated to study changes in various parameters after 6months treatment with mifepristone 50mg once a week. Baseline investigations were performed and menstrual blood loss was assessed using pictorial blood assessment charts. Fifty milligrams of mifepristone weekly was used, and patient assessed at 1 and 6month. They were also further followed up till 3months after stopping the drug to observe the changes in menstrual pattern, fibroid volume, hemoglobin and liver function tests. Baseline endometrial biopsy and another at 6month on cessation of drug therapy were done for all patients. Majority of the study population comprised of perimenopausal women, i.e., 41-45years (44%). Fifty percent of the patients were Para 2 and belonged to the perimenopausal age-group (18 out of 36). The dominant presenting symptom was menorrhagia associated with dysmenorrhea and pelvic pain. After 6months of treatment with mifepristone, the mean fibroid volume reduced from 204.33 to 113.16cm(3) (n=33); p≤0.001, and the percentage mean volume reduction of the fibroid in the study population was 44.57% (range 1.10-100%). Immediate reduction in bleeding PV was observed in 100%, and 88.89% (32/36) patients attained amenorrhea. The mean hemoglobin increased from 9.18 to 10.82g/dl (p=0.001). There was a transient rise in mean transaminases (AST/ALT) levels at 6months which reverted to normal at 9months follow-up. To conclude, 6months therapy with 50mg of mifepristone given weekly is efficacious and acceptable for the treatment of symptomatic leiomyoma, especially in a select group of patients. Although its use as a primary medical therapy is limited due to recurrence of fibroid after stopping treatment, it is useful for perimenopausal women whose myoma would regress after menopause, and younger infertile patients with small-size deep intramural myomas not easily accessible to either hysteroscopic or laparoscopic surgery. It is also beneficial as a preoperative adjunct, in patients with preoperative severe anemia and large fibroids where surgery is technically difficult. Mode of surgery can be changed to a less-invasive vaginal hysterectomy rather than an abdominal procedure.