From the Guidelines
New onset fibroids in a postmenopausal woman should be promptly evaluated with transvaginal ultrasound and endometrial sampling due to the increased risk of malignancy, as suggested by the 2024 update of the ACR Appropriateness Criteria for management of uterine fibroids 1. The natural history of fibroids is shrinkage and symptom resolution with menopause, so any new or growing pelvic mass in a postmenopausal woman should be investigated thoroughly. Some key points to consider in the evaluation and management of new onset fibroids in postmenopausal women include:
- The initial imaging study should be transvaginal ultrasound, followed by endometrial sampling if there is abnormal bleeding, and MRI may be needed for better characterization of the mass 1.
- Referral to a gynecologist is essential, and the patient should be scheduled for evaluation within 2-4 weeks.
- Management depends on symptoms, size of the fibroid, and risk factors, with asymptomatic small fibroids potentially being monitored with repeat imaging in 3-6 months, while symptomatic or rapidly growing fibroids typically require surgical intervention, usually hysterectomy in postmenopausal women.
- The concern in this population is that what appears to be a fibroid could actually be a leiomyosarcoma or other uterine malignancy, as estrogen levels naturally decline after menopause and fibroids typically shrink rather than appear or grow.
- Risk factors that increase suspicion include rapid growth, large size (>5cm), irregular borders on imaging, and postmenopausal bleeding, and hormone replacement therapy can sometimes contribute to fibroid growth in postmenopausal women and should be reviewed as part of the evaluation. Hysterectomy may be helpful in postmenopausal patients with symptomatic fibroids and a negative endometrial biopsy, as it provides definitive resolution of all fibroid-related symptoms and allows for pathologic evaluation of the uterus to confirm absence of malignancy 1. However, the potential benefits of hysterectomy must be weighed against the potential for increased surgical risk in this older cohort of patients, and the least invasive route for hysterectomy should be performed, with vaginal hysterectomy being associated with shorter operating times, a faster return to normal activities, and a better quality of life compared to abdominal hysterectomy 1.
From the Research
New Onset Fibroid in Post-Menopausal Woman
- The development of new onset fibroids in post-menopausal women is a topic of interest, with studies suggesting that hormone therapy may play a role in the growth of fibroids 2.
- A study published in 2018 found that hormone therapy in menopausal women with fibroids can have variable effects on the volume and size of the fibroids, with some studies demonstrating an increase in size of pre-existing asymptomatic fibroids and formation of new fibroids with higher doses of progestogen in combination therapy 2.
- The use of magnetic resonance imaging (MRI) has been explored as a tool for predicting the growth of fibroids, with one study finding that the measurement of pulsatility index of uterine arteries may be a possible screening tool before initiating hormone therapy in menopausal women with fibroids 2.
- Other treatment options for fibroids, such as magnetic resonance-guided focused ultrasound surgery, have also been studied, with some research suggesting that this method can be effective in reducing fibroid size and symptoms 3, 4, 5.
- The use of gonadotropin-releasing hormone (GnRH) agonists has also been explored as a potential treatment for fibroids, with one study finding that GnRH agonist treatment before uterine artery embolization can be effective in reducing fibroid volume 6.
- Overall, the management of new onset fibroids in post-menopausal women requires careful consideration of the potential risks and benefits of different treatment options, including hormone therapy, MRI-guided focused ultrasound surgery, and GnRH agonist treatment.
Treatment Options
- Hormone therapy: may have variable effects on fibroid growth, with potential risks and benefits 2.
- Magnetic resonance-guided focused ultrasound surgery: a non-invasive treatment option that can be effective in reducing fibroid size and symptoms 3, 4, 5.
- GnRH agonist treatment: may be effective in reducing fibroid volume before uterine artery embolization 6.
- Uterine artery embolization: a minimally invasive treatment option that can be effective in reducing fibroid size and symptoms 6.