Uterine fibroids (also known as uterine fibroma, leiomyoma, fibromyoma, and myoma) are the most common solid tumor of the female reproductive tract. (American College of Obstetricians and Gynecologists: ACOG Practice Bulletin, No. 16. Surgical Alternatives to Hysterectomy in the Management of Leiomyomas, 2000.) These benign smooth muscle tumors grow within the muscle layers of the uterus (subserosal, submucosal, or intramural), are intrauterine (intracavitary), or attach to the outside of the uterus by a thick pedunculated stalk. The etiology of these tumors is unknown, but leiomyomas contain estrogen-sensitive receptors. This explains why they often enlarge rapidly during pregnancy as estrogen levels surge, but tend to regress after menopause. Fibroid tumors vary in number and size. They can be microscopic or mimic a full-term uterus.

Although the true incidence of leiomyoma is unknown because many women are asymptomatic, it is estimated that from five percent to 80 percent of women are affected. (Am J Obstet Gynecol 2003;188:100.) In women of reproductive age, approximately 25 percent to 35 percent have fibroid tumors. (Fertil Steril 1981;36:433.) Women who are African-American, overweight, or older, however, appear to be at greater risk. (Br J Obstet Gynaecol 1990;97:285.)

The clinical presentation of uterine fibroids varies, and depends on the size, location, and number of tumors. Most fibroids are asymptomatic and inconsequential, but symptoms can range from abdominal fullness, menometrorrhagia, pain, urinary frequency or retention, dyspareuria, and constipation to infertility and gynecologic hemorrhage. Acute pain secondary to leiomyoma is uncommon, but can be caused by torsion of a pedunculated fibroid tumor or infarction of tissue within a tumor that has outgrown its blood supply. On physical examination, patients may have lower abdominal tenderness, a palpable suprapubic abdominal mass, bleeding from the cervical os, or a palpable uterine mass on pelvic examination.

The reported prevalence of fibroids in pregnancy ranges from 0.09 percent to 3.9 percent (Obstet Gynecol Clin NA 2006;33[1]:153), and can cause numerous potential antepartum and postpartum complications including miscarriage, preterm labor, placental abruption, preeclampsia, intrauterine growth restriction, disseminated intravascular coagulation, postpartum hemorrhage, and fetal malposition or anomalies.

Very few fibroid tumors are or become malignant, but rapidly growing lesions, particularly after menopause, should elicit concern. These lesions typically are diagnosed as leiomyosarcoma on histology.

ED evaluation and management depends on the severity of presentation. Uterine imaging including ultrasound, computerized tomography (CT) scan, and magnetic resonance imaging (MRI) may be helpful if the course of vaginal bleeding or intrabdominal mass is in question. Asymptomatic hemodynamically stable patients who are not critically anemic can be discharged with bleeding precautions, analgesics, and given a gynecological referral for outpatient management and possibly imaging. Obviously, standard resuscitation should be performed for those who are hemodynamically unstable.

Many potential treatment options for fibroids now exist. Although these are not offered by emergency physicians, it is helpful for us be familiar with them. In the past, a total hysterectomy or myomectomy was the standard treatment for fibroids; recently, minimally invasive alternatives have become available including laparoscopic management, hysteroscopic myomectomy, endometrial ablation, uterine artery embolization, hormone therapy, and high-intensity focused ultrasound, also known as magnetic resonance-guided focused ultrasound. (Am J Obstet Gynecol 2007;196[6]:601 and 2007;196[2]:184.)

Hysterectomy is the definitive treatment for fibroids because there is no possibility for recurrence. Currently, leiomyoma is the leading indication for hysterectomy in the United States, with more than 200,000 procedures performed annually for this indication alone. (Hysterectomy Surveillance-United States, 1994-1999. MMWR CDC Surveill Summ 2002;51[SS-5]:1.) Hysterectomy is a major intraabdominal procedure, however, with an overall complication rate of 17 percent to 23 percent. (Can Fam Phys 2007;53[2]:250.) Myomectomy, on the other hand, has the disadvantage of potential recurrence and the subsequent requirement for further surgery in 5.7 percent to 51 percent of patients. (Hum Reprod 2002;17[2]:253.)

Uterine fibroid embolization involves injecting an embolizing agent into both uterine arteries to interrupt the tumor blood supply. As a result, the avascular tumor shrinks without the need for surgery. (Hum Reprod 2002;17[2]:253.) Studies have reported the volume reduction ratio of fibroids treated by embolization to range from 36.7 percent to 70 percent three to 12 months after the procedure. Reported complications included postembolization syndrome, ovarian dysfunction, endometrial atrophy, sepsis, and in rare cases, death. (Am J Obstet Gynecol 2007;196[2]:184.)

The high-intensity focused ultrasound technique is a minimally invasive procedure that uses concentrated ultrasonic waves in combination with MRI guidance to convert acoustic energy into thermal energy at the fibroid foci. This results in thermal coagulation within seconds, at temperatures ranging from 60°C to 90°C, while sparing local areas including the acoustic pathway. (Am J Obstet Gynecol 2007;196[2]:184.) This technique is relatively new, and was approved by the FDA only in 2005.

This patient was found to have a 21 cm × 11 cm × 17 cm fibroid and a hemoglobin of 5 gm/dL. She was admitted to the hospital and received a blood transfusion. She refused any definitive therapies, and has since been re-evaluated in the ED multiple times for significant vaginal bleeding and severe anemia requiring multiple blood transfusions.

Wiler, Jennifer L. MD, MBA

Dr. Wiler is the assistant chief of clinical operations in the department of emergency medicine at Washington University in St. Louis.

Emergency Medicine News:Volume 30(1)January 2008p 20