Fibroids

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Fibroids, aka leiomyomas, are non-cancerous overgrowths of fibromuscular tissues within the uterine wall. They’re very common, affecting 20-80% of women by the age of 50 (depending on the population). Additionally, fibroids for 50% of women are completely asymptomatic.

Many patients will inquire about cancer risk with these benign “tumors,” particularly given the bad press around power morcellation. Fibroids in general do not increase one’s risk for malignancy; the risk of sarcomas in leiomyomas range between 0.05-0.28% (very rare).

Risk factors for fibroids include age (older > younger), black race, obesity, family history of fibroids, nulliparity, vitamin D deficiency, food additive consumption, and use of soy milk, strangely enough.

Fibroids are classified using a FIGO classification system based on their location:

So if fibroids half the time don’t cause problems, how and why do they cause problems?

The most common symptom of fibroids is heavy, prolonged menstrual bleeding. Fibroids do not necessarily rule out the risk of endometrial malignancy, so for those at risk, you should still do an endometrial cavity evaluation with EMB or hysteroscopy D&C. However, the bleeding from fibroids can be significant. The degree of bleeding is correlated often with the location of the fibroid, with size of secondary importance. Submucosal fibroids most frequently cause significantly heavy bleeding. Intramural fibroids can also cause this. Subserosal fibroids are rarely associated with heavy bleeding. How and why does this bleeding occur? It’s unclear, but may include abnormalities of uterine vasculature.

Another common symptom of fibroids are “bulk” symptoms. This is due to the size or location of a fibroid causing mass effect. This often manifests as pelvic pain/pressure that is chronic, intermittent, and dull; urinary tract or bowel issues such as frequency, difficulty emptying, or constipation; painful menses or intercourse; and venous compression rarely, similarly to a gravid uterus causing vena cava compression and increasing VTE risk. Clinically you might also see fibroid degeneration, where the fibroid has outstripped its blood supply and is necrosing, which leads to pain, leukocytosis, low grade fever, and uterine tenderness.

The final category of symptoms are reproductive issues. If a fibroid distorts the endometrial cavity, it may result in difficulty conceiving or increased risk of miscarriage. The links here are suspect as large, observational studies looking at these problems have many other confounding factors (i.e., increasing age). That said, fibroids have also been noted to have association with adverse pregnancy outcome as well, including placental abruption, fetal growth restriction, malpresentation, and preterm labor and birth.

Therapy options can be broken down into “expectant management,” medical treatment, and surgical treatment.  

For medical therapies, there are multiple options:

  • Hormone therapies - really just to treat bleeding; doesn’t really help that much with other symptoms like bulk-related or reproductive issues.

    1. Combined estrogen-progesterone contraceptives - first line in treatment of AUB, but there is a high conversion rate to surgery in 5 year period.

    2. Levonorgestrel IUD - no randomized trials evaluating IUD for HMB related to fibroids. 

      1. There is a decrease in bleeding and increase in hematocrit in observational studies; however, distortion of cavity due to fibroid is a relative contraindication .

    3. Progestin treatments (ie. implant, injection, pills) - conflicting info about whether or not they can increase size of fibroid 

      1. Can be considered for treatment of mild symptoms especially in women that desire contraception 

    4. PRMs (progesterone receptor modulators) - not currently available in most countries

      1. Ulipristal acetate has been used outside the US, but stopped because of rare cases of liver toxicity; has been shown to decrease HMB 

      2. Mifepristone - not currently approved for treatment of fibroid; has been shown to reduce uterine volume by 26-74%, which is comparable to GnRH agonists! However, no availability in the doses that are used to treat fibroids (ie. 5-50 mg/day compared to 200mg for abortion) 

    5. GnRH agonists - most effective medical therapy for uterine fibroids; only available as injection.

      1. Initially increases release of gonadotropins, but then there is desensitization and downregulation to hypogonadotropic, hypogonadal state; a “medical menopause” if you will.

      2. Most women will develop amenorrhea or betterment of bleeding, and there is significant reduction of uterine size 

      3. Effect is temporary, and symptoms quickly return after you stop using it

      4. Can lead to menopausal issues due to hypoestrogenic state = Vasomotor symptoms, but also BONE LOSS

        1. Should not use for >6 months without add-back therapy: combined estrogen-progesterone or just progesterone in the form of 0.625 mg of conjugated estrogen and 2.5mg of medroxyprogesterone acetate or 5 mg norethindrone acetate);

        2. Usually GnRH agonists are used pre-operatively to shrink fibroid, as a “bridge” to surgery.

    6. GnRH antagonists - pretty new for this stuff! 

      1. Also induces hypoestrogenic state, but they are oral, not injections! Can lead to all the bad things that GnRH agonists can.

      2. The one available in the USA is Elagolix (Orilissa) 

      3. Also need add-back therapy if you want to use it long term.

    7. Aromatase Inhibitors - small studies show decrease in size of fibroids; not FDA approved 

    • Antifibrinolytic agents such as TXA are not well studied in HMB related to fibroids specifically, but is used for heavy bleeding in general.

    • NSAIDs - not extensively studied for HMB in fibroids; doesn’t decrease bleeding much, but can help with pain.

Surgical therapy is an alternative choice, particularly if medical management fails, or for bulk or infertility-related symptoms.  

  • Myomectomy 

    1. Usually for people who aren’t done with childbearing or want to retain their uterus.

    2. Try and complete it minimally invasively if possible for decreased morbidity; this includes laparoscopically, robotically, or hysteroscopically if possible.

    3. Otherwise will need to do a laparotomy.

  • Endometrial ablation 

    1. Purely for bleeding symptoms.

    2. However, some devices are only designed to be used in a normal cavity and not.a distorted cavity. Also, will not help with bulk symptoms.

    3. Relatively high rate of re-intervention for treatment failure.

  • Uterine artery embolism 

    1. Can lead to shrinkage of fibroids 30-46%.

    2. However, those with larger uteri and/or fibroids are at higher risk of failure.

    3. Relatively high rate of re-intervention for treatment failure. 

  • Hysterectomy 

    1. Suggested for women who are have severe hemorrhage not responsive to other treatments, done with childbearing and have other issues (like EIN, endometriosis, etc) that could be eliminated by hysterectomy, failed prior minimally invasive therapies for fibroids, or done with childbearing and want definitive treatment of symptoms.

    2. Main advantage: eliminates symptoms and any recurrent problems from fibroids.

    3. Morbidity may outweigh benefits if there is a solitary subserosal fibroid, a pedunculated fibroid, or a submucosal fibroid that is easily removed by hysteroscopy.

    4. Minimally invasive hysts should be pursued when possible to decrease morbidity.