Uterine leiomyoma: Clinical sciences

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Introduction0:00–1:45

Uterine leiomyomas, also known as fibroids, are benign, solid neoplasms made up of smooth muscle cells and fibroblasts. They can vary in size and location in the uterus, including intramural that are found within the width of the myometrium; submucosal that grow towards the mucosa of the uterus; subserosal that are found near the outer layer or serosa of the uterus; and pedunculated fibroids that grow on a stalk out of the uterine walls, either inside and outside the uterus.
Uterine leiomyomas are very common, and the majority of women have at least one by menopause. They are often asymptomatic, but symptomatic leiomyomas can cause a variety of issues, such as heavy bleeding and pelvic pressure or pain.
In fact, leiomyoma is one of the important causes of abnormal uterine bleeding or heavy menstrual bleeding, which can be easily remembered with the mnemonic PALM COEIN.
This stands for Polyps, Adenomyosis, Leiomyoma, Malignancy, Coagulopathy, Ovulatory dysfunction, Endometrial, Iatrogenic, and Not yet classified.
Additionally, leiomyomas can cause infertility in some patients, and depending on their location in the uterus, they can even be associated with recurrent pregnancy loss.
When assessing a patient who presents with a chief concern suggesting they have a uterine leiomyoma, your first step is to obtain a focused history and physical.

Focused H&P1:45–3:06

Patients may report prolonged or heavy menstrual bleeding; anemia; or symptoms of uterine enlargement such as pelvic pressure or pain, urinary frequency, and constipation.
While obtaining a history, pay attention to certain risk factors for uterine leiomyomas, such as premenopausal status, a family history of leiomyomas, increasing interval since last birth, hypertension, and obesity.
On a physical exam you may note an enlarged uterus or an irregular uterine contour.Here’s a clinical pearl! Black individuals have a 2 to 3 times higher rate of having uterine leiomyomas compared to white individuals.
Due to racial disparities and social determinants of health, black patients also develop leiomyomas earlier and have worse clinical symptoms including higher rates of anemia and larger uteri at the time of diagnosis.
Now, back to your patient! Based on your history and physical exam findings, you should suspect uterine leiomyoma and order a pelvic ultrasound.

Imaging3:06–5:46

If there is no evidence of a leiomyoma on ultrasound, you should consider an alternative diagnosis. Since there are multiple types of leiomyomas, ultrasound findings can vary, but generally, you’ll see a smooth and regular myometrial mass.
Let's talk about the different types of leiomyomas. The International Federation of Gynecology and Obstetrics, or FIGO, created a standardized leiomyoma subclassification system that’s used to describe the location of leiomyomas in the uterus.
Submucosal leiomyomas are numbered 0 to 2. Category 0 is intracavitary pedunculated, category 1 is less than 50% intramural and category 2 greater than or equal to 50% intramural.
Categories 3 and 4 are both intramural but 3 contacts the endometrium. Subserosal leiomyomas are numbered 5 to 7: category 5 is greater than or equal to 50% intramural, category 6 is less than 50% intramural and category 7 is subserosal pedunculated.
Category 8 encompasses others, which includes cervical leiomyomas. Keep in mind that you can also have a leiomyoma that prolapses through the cervix!Here’s another clinical pearl!
A standard pelvic ultrasound is a helpful tool, but it can be hard to distinguish all the categories of leiomyomas. A subserosal pedunculated leiomyoma is generally best diagnosed with a pelvic ultrasound, while others need further workup.
If you are suspicious of a submucosal leiomyoma, a sonohysterogram can be a useful tool. This is performed by injecting a small amount of saline into the uterine cavity during a transvaginal ultrasound to open up the endometrial cavity and inspect the contours of the endometrium.
Hysteroscopy, where a camera is inserted into the endometrial cavity along with saline, can be used to visually diagnose and treat submucosal leiomyomas too.
An MRI can be used for surgical planning to map out a large fibroid uterus.Okay, now that you’ve diagnosed leiomyoma, let's talk about treatment options!

Treatment5:46–11:00

The main categories for management are expectant, medical, procedural, and surgical. It's important to discuss all the options with your patient and make a treatment plan based on your patient's goals.Expectant management is appropriate for asymptomatic leiomyomas and for symptomatic patients who do not desire intervention.
This includes leiomyomas found incidentally on imaging. Remember the majority of leiomyomas are asymptomatic, with only a quarter of leiomyomas being clinically significant enough to require intervention.The second treatment category is medical management, which is typically used if the goal is to improve heavy bleeding that could be causing anemia.
Medications include oral GnRH antagonists, such as elagolix or relugolix with hormonal add-back therapy; the levonorgestrel intrauterine system or IUS; and contraceptive hormones, such as combined oral birth control pills, progesterone only pills and depot medroxyprogesterone.
Both the oral GnRH antagonists and levonorgestrel IUS have been shown to significantly improve bleeding. However, Elagolix and relugolix can cause hypoestrogenic effects such as hot flashes, which are improved with hormonal add-back therapy.
It's important to remember that they can only be used for up to 24 months due to concerns for bone loss. Additionally, the levonorgestrel IUS has an increased risk of expulsion if the uterine cavity is distorted by leiomyomas.
Another medical therapy is a GnRH agonist, like depot leuprolide. It helps decrease uterine size along with bleeding and often is used as short-term bridge therapy before other interventions, like surgery.
Keep in mind that GnRH antagonists and agonists are not birth control, so you should always discuss family planning goals with your patient, and prescribe contraception as indicated!
Lastly, patients may get medical management with tranexamic acid, which is an antifibrinolytic medication that helps reduce heavy bleeding.
The third treatment category is procedural, with the most common modality being uterine artery embolization or UAE. The goal of a UAE is to decrease blood flow to the uterus and therefore reduce uterine size and bleeding.
This is a good option for a patient who wants to avoid surgical intervention or desires uterine preservation. However, there is limited data on reproductive outcomes after UAE, and it’s often not recommended for those who desire future fertility.
UAE also carries a risk of needing further intervention. Newer procedures include radiofrequency ablation and focused ultrasound destruction.
The last category is surgical management with either myomectomy or hysterectomy. Both can be completed either by laparoscopy, robotic-assisted laparoscopy, or open techniques.
Myomectomy is a good option if your patient desires uterine preservation or future fertility. However, be sure to counsel them on the risk of recurrent leiomyomas, as well as the possible risk of uterine rupture with labor in cases where the myomectomy entered the uterine cavity; in fact, for patients who had prior myomectomy that involves large dissections into the uterine wall, vaginal delivery may not be safe, so they might require C-section.
A hysteroscopic myomectomy can also be performed if the leiomyoma is submucosal category 0 or 1. On the flip side, hysterectomy is the definitive surgical management for leiomyomas.
In fact, leiomyomas are the leading indication for hysterectomy. When performing a hysterectomy, it’s ideal to choose the most minimally invasive approach while taking into consideration the size and shape of the uterus.
A vaginal approach is another option for hysterectomy, but its use is limited with larger uteri.One last clinical pearl!
You should always keep in mind that a uterine mass might be uterine leiomyosarcoma, which is a rare but aggressive form of uterine cancer.
Preoperative diagnosis is not reliable, so always follow up on pathology to rule out this disease. Another thing to keep in mind is that power morcellation, which is a way of removing a large uterus during a minimally invasive hysterectomy, can potentially spread an unsuspected leiomyosarcoma.
Because of this, its use has been minimized. Alright, as a quick recap… Uterine leiomyomas are common, benign neoplasms of the uterus made up of smooth muscle.

Review11:00–12:02

They can vary in size and location. The most important diagnostic tool is a pelvic ultrasound, but further work-up might be necessary to determine the category of leiomyoma and appropriate treatment plan.
The majority of leiomyomas are asymptomatic and do not require intervention, just expectant management. For those that are symptomatic, treatment is divided into four main categories that include expectant management for patients who don’t desire intervention; medical management with GnRH antagonists and hormonal add-back therapy, the levonorgestrel IUS, contraceptive hormones, a GnRH agonist, and tranexamic acid; procedural management with a UAE; and surgical management with either a myomectomy or hysterectomy.