UPA effects on endometrium - what is the significance?

Area of Science:

• Gynecology
• Pharmacology
• Oncology

Background:

• Selective progesterone receptor modulators (SPRMs) show antiproliferative effects on uterine fibroids.
• Ulipristal acetate (UPA) is available but underutilized due to physician concerns regarding endometrial safety.
• This study addresses the safety and efficacy of UPA in treating symptomatic uterine fibroids.

Purpose of the Study:

• To evaluate the antiproliferative effects of Ulipristal acetate (UPA) on uterine fibroids.
• To assess the safety of UPA treatment on the endometrium in premenopausal women.
• To investigate the relationship between UPA treatment, endometrial changes, and Ki67 expression.

Main Methods:

• An observational study involving 57 premenopausal women with symptomatic uterine fibroids.
• Patients received UPA 5 mg daily for 12-13 weeks.
• Fibroid dimensions, endometrial thickness, and progesterone receptor modulator associated endometrial changes (PAEC) including Ki67 immunoexpression were assessed pre- and post-treatment.

Main Results:

• UPA treatment led to a decrease in fibroid dimensions and endometrial thickness.
• Pathological examination revealed: Absent PAEC (APAEC) in 26.8%, Minimally PAEC (MPAEC) in 60.7%, and Extensive PAEC (EPAEC) in 12.5% of cases.
• EPAEC correlated with larger fibroids, higher Ki67 expression (mean 69%), and occurred more frequently in older women.

Conclusions:

• UPA treatment effectively reduced uterine fibroid size and improved patient symptoms.
• Three months of UPA is safe regarding endometrial atypia, with EPAEC linked to Ki67 antigen.
• Longer UPA treatment protocols require further investigation into endometrial proliferative potential.