Leiomyoma of the uterus (Fibroid Tumor)

Introduction

Essentials of Diagnosis

• Irregular enlargement of the uterus (may be asymptomatic).
• Heavy or irregular vaginal bleeding, dysmenorrhea.
• Acute and recurrent pelvic pain if the tumor becomes twisted on its pedicle or infarcted.
• Symptoms due to pressure on neighboring organs (large tumors).

General Considerations

Uterine leiomyoma is the most common benign neoplasm of the female genital tract. It is a discrete, round, firm, often multiple uterine tumor composed of smooth muscle and connective tissue. The most convenient classification is by anatomic location: (1) intramural, (2) submucous, (3) subserous, (4) intraligamentous, (5) parasitic (ie, deriving its blood supply from an organ to which it becomes attached), and (6) cervical. A submucous myoma may become pedunculated and descend through the cervix into the vagina.

Clinical Findings

A. Symptoms and Signs In nonpregnant women, myomas are frequently asymptomatic. However, they can cause urinary frequency, dysmenorrhea, heavy bleeding (often with anemia), or other complications due to the presence of an abdominal mass. Occasionally, degeneration occurs, causing intense pain. Infertility may be due to a myoma that significantly distorts the uterine cavity.

B. Laboratory Findings

Hemoglobin levels may be decreased as a result of blood loss, but in rare cases polycythemia is present, presumably as a result of the production of erythropoietin by the myomas.

C. Imaging

Ultrasonography will confirm the presence of uterine myomas and can be used sequentially to monitor growth. When multiple subserous or pedunculated myomas are being followed, ultrasonography is important to exclude ovarian masses. MRI can delineate intramural and submucous myomas accurately. Hysterography or hysteroscopy can also confirm cervical or submucous myomas.

Differential Diagnosis

Irregular myomatous enlargement of the uterus must be differentiated from the similar but symmetric enlargement that may occur with pregnancy or adenomyosis (the presence of endometrial glands and stroma in the myometrium). Subserous myomas must be distinguished from ovarian tumors. Leiomyosarcoma is an unusual tumor occurring in 0.5% of women operated on for symptomatic myoma. It is very rare under the age of 40 and increases in incidence thereafter.

Treatment

A. Emergency Measures If the patient is markedly anemic as a result of long, heavy menstrual periods, preoperative treatment with depot medroxyprogesterone acetate, 150 mg intramuscularly every 28 days, or danazol, 400-800 mg orally daily, will slow or stop bleeding, and medical treatment of anemia can be given prior to surgery. Emergency surgery is required for acute torsion of a pedunculated myoma. The only emergency indication for myomectomy during pregnancy is torsion; abortion is not an inevitable result.