What are uterine leiomyomas (fibroids)?

From the Guidelines

Uterine leiomyomas (fibroids) are benign tumors that develop in or around the uterus, composed of smooth muscle cells and fibroblasts, and are the most common benign tumor in patients of reproductive age. They can vary in size, number, and location, and may cause symptoms such as heavy and prolonged uterine bleeding, pelvic pain, bulk symptoms, and reproductive dysfunction 1. According to 1, fibroids are the most common neoplasm of the uterus, and their prevalence varies with race, with Black women having an estimated incidence of fibroids by age 50 exceeding 80%, whereas White women have an incidence approaching 70%.

• Key characteristics of uterine fibroids include:
  • Composed of benign smooth muscle cells embedded in an extracellular matrix of collagen, fibronectin, and proteoglycan 1
  • Can cause symptoms such as menorrhagia, dysmenorrhea, pelvic pain and pressure, urinary urgency and frequency, and constipation 1
  • May impair fertility and/or cause obstetric complications 1
  • Can be diagnosed with pelvic ultrasound (US) or MRI, which further characterizes fibroid location, size, and number 1
  • Treatment options range from medical therapy to surgery, including hysterectomy, myomectomy, endometrial ablation, uterine fibroid embolization (UFE), MR-guided focused ultrasound (MRgFUS), and laparoscopic radiofrequency ablation 1

From the Research

Definition and Prevalence of Uterine Leiomyomas (Fibroids)

• Uterine fibroids (UFs) are benign tumors that arise from a single genetically altered mesenchymal stem cell under the influence of gonadal hormones 2
• They are the most common female benign pelvic tumors, affecting >60% of patients aged 30-44 years 3
• UFs are non-cancerous overgrowths of the smooth muscle in the uterus, and as they grow, some cause problems such as heavy menstrual bleeding, pelvic pain, discomfort during sexual intercourse, and rarely pregnancy complications or difficulty becoming pregnant 4
• Fibroids are benign, hormone-dependent tumours of uterine smooth muscle and connective tissue, commonly asymptomatic, but can cause symptoms such as heavy menstrual bleeding and pelvic pressure symptoms 5

Symptoms and Effects of Uterine Fibroids

• Uterine fibroid symptoms include abnormal menstrual bleeding leading to anaemia, tiredness, chronic vaginal discharge, and pain during periods 6
• Other symptoms include protrusion of the abdomen, pain during intercourse, dysfunctions of bladder/bowel leading to urinary incontinence/retention, pain, and constipation 6
• UFs often present with abnormal uterine bleeding (AUB), pelvic fullness, and may have deleterious effects on fertility 2
• Heavy menstrual bleeding and iron deficiency (ID) and ID anemia are common complaints associated with UFs 3

Treatment Options for Uterine Fibroids

• Medical treatments used for UFs-related abnormal uterine bleeding include symptomatic agents, such as nonsteroidal antiinflammatory drugs and tranexamic acid, and hormonal therapies, including combined oral contraceptives, gonadotropin-releasing hormone agonists or antagonists, levonorgestrel intrauterine systems, selective progesterone receptor modulators, and aromatase inhibitors 3
• Surgical options include fertility-sparing treatments, such as myomectomy, or nonconservative options, such as hysterectomy, especially in perimenopausal women who are not responding to any treatment 3
• Radiologic interventions are also available: uterine artery embolization, high-intensity focused ultrasound or magnetic resonance-guided focused ultrasound, and radiofrequency ablation 3