Uterine Fibroid

Compiled and Summarized by Alex
Uterine fibroids are noncancerous growths of the uterus that often appear during childbearing years. Also called fibromyomas, leiomyomas or myomas, uterine fibroids aren't associated with an increased risk of uterine cancer and almost never develop into cancer.

As many as three out of four women have uterine fibroids, but most are unaware of them because they often cause no symptoms. The doctor may discover them incidentally during a pelvic exam or prenatal ultrasound.

In general, uterine fibroids cause no problems and seldom require treatment. Medical therapy and surgical procedures can shrink or remove fibroids if there is no discomfort or troublesome symptoms. Rarely, fibroids can require emergency treatment if they cause sudden, sharp pelvic pain.

Signs and Symptoms

Uterine fibroids are often asymptomatic. Rapidly enlarging tumors may cause pelvic pain. They are a common cause of heavy or irregular menstrual bleeding. In women of child bearing age, these tumors may produce infertility. Excessive blood loss can lead to signs of anemia, including fatigue, shortness of breath, rapid heart rate and pallor.

Causes

Uterine fibroids develop from the smooth muscular tissue of the uterus (myometrium). A single cell reproduces repeatedly, eventually creating a pale, firm, rubbery mass distinct from neighboring tissue.

Fibroids range in size from seedlings, undetectable by the human eye, to bulky masses that can distort and enlarge the uterus. They can be single or multiple, in extreme cases expanding the uterus so much that it reaches the rib cage.

Doctors don't know the cause of uterine fibroids, but research and clinical experience point to several factors:

· Genetic alterations. Many fibroids contain alterations in genes that code for uterine muscle cells.

· Hormones. Estrogen and progesterone, two hormones that stimulate development of the uterine lining in preparation for pregnancy, appear to promote the growth of fibroids. Fibroids contain more estrogen and estrogen receptors than do normal uterine muscle cells.

· Other chemicals. Substances that help the body maintain tissues, such as insulin-like growth factor, may affect fibroid growth.

Diagnosis

Uterine fibroids are frequently found incidentally during a routine pelvic exam. The doctor may feel irregularities in the shape of the uterus through the abdomen, suggesting the presence of fibroids.

Ultrasound

If confirmation is needed, the doctor may obtain an ultrasound — a painless exam that uses sound waves to obtain a picture of the uterus — to confirm the diagnosis and to map and measure fibroids. A doctor or technician moves the ultrasound device (transducer) over the abdomen (transabdominal) or places it inside the vagina (transvaginal) to obtain images of the uterus.

Transvaginal ultrasound provides more detail because the probe is closer to the uterus. Transabdominal ultrasound visualizes a larger anatomic area. Sometimes, fibroids are discovered during an ultrasound conducted for a different purpose, such as during a prenatal ultrasound.

Other imaging tests

If traditional ultrasound doesn't provide enough information, the doctor may order other imaging studies, such as:

· Hysterosonography. This ultrasound variation uses sterile saline to expand the uterine cavity, making it easier to obtain interior images of the uterus. This test may be useful if there is heavy menstrual bleeding despite normal results from traditional ultrasound.

· Hysterosalpingography. This technique uses a dye to highlight the uterine cavity and fallopian tubes on X-ray images. The doctor may recommend it if infertility is a concern. In addition to revealing fibroids, it can help the doctor determine if the fallopian tubes are open.

· Hysteroscopy. The doctor inserts a small, lighted telescope called a hysteroscope through the cervix into the uterus. The tube releases a gas or liquid to expand the uterus, allowing the doctor to examine the walls of the uterus and the openings of the fallopian tubes. A hysteroscopy can be performed in the doctor's office.

Imaging techniques that may occasionally be necessary include computerized tomography (CT) and magnetic resonance imaging (MRI).

Other tests

If the client is experiencing abnormal vaginal bleeding, the doctor may want to conduct other tests to investigate potential causes. He or she may order a complete blood count (CBC) to determine if there is iron deficiency anemia because of chronic blood loss. The doctor may also order blood tests to rule out bleeding disorders and to determine the levels of reproductive hormones produced by the ovaries.

Pathogenesis

For complete detail. See link.

Pathophysiology

Smooth-muscle tumors of uterine origin encompass a broad family of neoplasms. The leiomyoma, by far the most common of all the neoplasms, generally is hormone sensitive, with rates of growth semiquantitatively related to estrogen and progesterone receptor levels. Several forms of degenerative change can occur in the leiomyoma. The most common is hyaline degeneration, which is important in that it should not be mistaken for the coagulative tumor cell necrosis seen in leiomyosarcoma. Red degeneration (necrobiosis) is a form of degeneration that occurs characteristically but not exclusively in pregnancy, and the process is often the cause of pain and fever. Several forms of treatment have been used medically in the treatment of leiomyoma. Gonadotropin-releasing hormone analogs or agonists or selective arterial embolization with polyvinylformaldehyde particles may lead to substantial degeneration or infarction of the leiomyoma, respectively. Several variants of leiomyoma, the cellular and symplastic leiomyomas, are important to recognize, as they can be misinterpreted as sarcoma. In addition, there are two unusual growth patterns of leiomyoma that are important to recognize. Both the benign metastasizing leiomyoma and disseminated peritoneal leiomyomatosis are found outside the uterus, and neither is malignant. Recent studies offer insights into their origin and hormonal influences. From a diagnostic and therapeutic point of view, the leiomyosarcoma, while rare, is clinically of great import. Coagulative necrosis, cytologic atypia, and mitotic counts are all important in diagnosing the condition.

Prevention

Although researchers continue to study the causes of fibroid tumors, little scientific advice is available on how to prevent them. Preventing uterine fibroids may not be possible, but you can take comfort in the fact that only a small percentage of these tumors require treatment.

Treatment

There's no single best approach to uterine fibroid treatment. Many treatment options exist. In most cases, the best action to take after discovering fibroids is simply to be aware they are there.

Watchful waiting

If you're like most women with uterine fibroids, you have no signs or symptoms. In your case, watchful waiting (expectant management) could be the best course. Fibroids aren't cancerous. They rarely interfere with pregnancy. They usually grow slowly and tend to shrink after menopause when levels of reproductive hormones drop. This is the best treatment option for a large majority of women with uterine fibroids.

Medications

Medications for uterine fibroids target hormones that regulate menstrual cycle, treating symptoms such as heavy menstrual bleeding and pelvic pressure. They don't eliminate fibroids, but may shrink them. Medications include:

· Gonadotropin-releasing hormone (Gn-RH) agonists. To trigger a new menstrual cycle, a control center in the brain called the hypothalamus manufactures gonadotropin-releasing hormone (Gn-RH). The substance travels to the pituitary gland, a tiny gland also located at the base of the brain, and sets in motion events that stimulate the ovaries to produce estrogen and progesterone.

Medications called Gn-RH agonists (Lupron, Synarel, others) act at the same sites that Gn-RH does. But when taken as therapy, a Gn-RH agonist produces the opposite effect to that of the natural hormone. Estrogen and progesterone levels fall, menstruation stops, fibroids shrink and anemia often improves.

· Androgens. The ovaries and the adrenal glands, located above your kidneys, produce androgens, the so-called male hormones. Given as medical therapy, androgens can relieve fibroid symptoms.

Danazol, a synthetic drug similar to testosterone, has been shown to shrink fibroid tumors, reduce uterine size, stop menstruation and correct anemia. However, occasional unpleasant side effects such as weight gain, dysphoria (feeling depressed, anxious or uneasy), acne, headaches, unwanted hair growth and a deeper voice, make many women reluctant to take this drug.

· Other medications. Oral contraceptives or progestins can help control menstrual bleeding, but they don't reduce fibroid size. Nonsteroidal anti-inflammatory drugs (NSAIDs), which are not hormonal medications, are effective for heavy vaginal bleeding unrelated to fibroids, but they don't reduce bleeding caused by fibroids.

Hysterectomy

This operation — the removal of the uterus — remains the only proven permanent solution for uterine fibroids. But hysterectomy is major surgery. It ends the ability to bear children, and if elected to have ovaries removed also, it brings on menopause and the question of whether you'll take hormone replacement therapy.

Myomectomy

In this surgical procedure, the surgeon removes the fibroids, leaving the uterus in place. If you want to bear children, you might choose this option. With myomectomy, as opposed to a hysterectomy, there is a risk of fibroid recurrence. There are several ways a myomectomy can be done:

· Abdominal myomectomy. If having multiple fibroids, very large or very deep fibroids, the doctor may use an open abdominal surgical procedure to remove the fibroids.

· Laparoscopic myomectomy. If the fibroids are small and few in number, the client and the doctor may opt for a laparoscopic procedure, which uses slender instruments inserted through small incisions in the abdomen to remove the fibroids from the uterus. The doctor views the abdominal area on a remote monitor via a small camera attached to one of the instruments.

· Hysteroscopic myomectomy. This procedure may be an option if the fibroids are contained inside the uterus (submucosal). A long, slender scope (hysteroscope) is passed through the vagina and cervix and into the uterus. The doctor can see and remove the fibroids through the scope. This procedure is best performed by a doctor experienced in this technique.

Variations of myomectomy — in which uterine fibroids are destroyed without actually removing them — include:

· Myolysis. In this laparoscopic procedure, an electric current destroys the fibroids and shrinks the blood vessels that feed them.

· Cryomyolysis. In a procedure similar to myolysis, cryomyolysis uses liquid nitrogen to freeze the fibroids.

The safety, effectiveness and associated risk of fibroid recurrence of myolysis and cryomyolysis have yet to be determined.

· Endometrial ablation. This treatment, performed with a hysteroscope, uses heat to destroy the lining of the uterus, either ending menstruation or reducing the menstrual flow. Endometrial ablation is effective in stopping abnormal bleeding, but doesn't affect fibroids outside the interior lining of the uterus.

Uterine artery embolization

Small particles injected into the arteries supplying the uterus cut off blood flow to fibroids, causing them to shrink. This technique is proving effective in shrinking fibroids and relieving the symptoms they can cause. Advantages over surgery include:

· No incision
· Shorter recovery time

Complications may occur if the blood supply to the ovaries or other organs is compromised.

Focused ultrasound surgery

MRI-guided focused ultrasound surgery (FUS), approved by the Food and Drug Administration in October 2004, is a newer treatment option for women with fibroids. Unlike other fibroid treatment options, FUS is noninvasive and preserves the uterus.

This procedure is performed while the client is inside of a specially crafted MRI scanner that allows doctors to visualize the anatomy, and then locate and destroy (ablate) fibroids inside the uterus without making an incision. Focused high-frequency, high-energy sound waves are used to target and destroy the fibroids. A single treatment session is done in an on- and off-again fashion, sometimes spanning several hours. Initial results with this technology are promising, but its long-term effectiveness is not yet known.

Notes to consider before deciding

Before making a decision, consider the pros and cons of all available treatment options in relation to your particular situation. Remember, most women don't need any treatment for uterine fibroids.

Complications

Although uterine fibroids usually aren't dangerous, they can cause discomfort and may lead to complications such as anemia from heavy blood loss. In rare instances, fibroid tumors can grow out of the uterus on a stalk-like projection. If the fibroid twists on this stalk, a sudden, sharp, severe pain in the lower abdomen may develop. If so, seeking medical care is strongly recommended. Surgery may be needed.

Pregnancy and fibroids

Because uterine fibroids typically develop during the childbearing years, women with fibroids are often concerned about their chances of a successful pregnancy.

Fibroids usually don't interfere with conception and pregnancy, but they can occasionally affect fertility. They may distort or block the fallopian tubes, or interfere with the passage of sperm from the cervix to the fallopian tubes. Submucosal fibroids may prevent implantation and growth of an embryo.

Research indicates that pregnant women with fibroids are at slightly increased risk of miscarriage, premature labor and delivery, abnormal fetal position, and separation of the placenta from the uterine wall. But not all studies confirm these associations. Furthermore, complications vary based on the number, size and location of fibroids. Multiple fibroids and large submucosal fibroids that distort the uterine cavity are the type most likely to cause problems. A more common complication of fibroids in pregnancy is localized pain, typically between the first and second trimesters. This is usually easily treated with pain relievers.

In most cases, fibroids don't interfere with pregnancy and treatment isn't necessary. It was once believed that fibroids grew faster during pregnancy, but multiple studies suggest otherwise. Most fibroids remain stable in size, although some increase or decrease slightly, usually in the first trimester.

If there are fibroids and the patient experienced repeated pregnancy losses, the doctor may recommend removing one or more fibroids to improve the chances of carrying a baby to term, especially if no other causes of miscarriage can be found and the fibroids distort the shape of the uterine cavity.

Doctors usually don't remove fibroids in conjunction with a Caesarean section because of the high risk of excessive bleeding.

References:

http://www.mayoclinic.com
Served as primary source.

http://www.myelectronicmd.com
Served as reference.

http://www.ehponline.org
Source for Pathophysiology.

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