Fibroids

The Uterus

Layers of the Uterus The uterus has three main layers, starting from inside to

outside: Endometrium Myometrium Perimetrium

Fibroids

Leiomyoma, Fibromyoma, Myoma Most common benign uterine tumor. Leading cause of hysterectomy in the US. Estimated 50% or greater of all women eventually develop

fibroid. A minority, 20 to 30% of these women are symptomatic Most frequently symptomatic ages 30s & 40s. More common in AA than White females. It is an estrogen sensitive tumor: may enlarge during pregnancy. Not a precursor for Leiomyosarcoma (the malignant tumor of the

uterus)

Tumor characteristics Undergoes: Degeneration Dystrophic calcification Hyalinization: the reason for the term “fibroids” Small: symptomatic if located within the uterine cavity Large: Usually go unnoticed and located outside of the

uterus

Risk Factors

African American 2-3 times greater risk than white women.

Obesity 21 % Increased risk for each 10 kg increase in weight. Increased conversion of androgen to estrone in obese women.

Family history 1st degree relative, 3-5 times more risk of developing fibroids.

Diet Meat, ham and beef increase risk.

Hypertension Every 10 mmHg in diastolic pressure there was an 8% increase in

diagnosis of unterine fibroid.

Symptoms Symptoms depend on size and location Menorrhagia: when located in the submucosa, is the most common symptom.

This may also lead to Iron deficieny anemia. Painful menstruation Painful sexual intercourse Pressure on bladder leading to: Frequency, urgency, incontinence Abnormal gynecologic hemorrhage Abdominal discomfort or bloating Pressure on colon: constipation, painful defecation Backache Some cases infertility but only accounts for 3% of cases; in such cases a

fibroid is located in submucosal position and it is thought that this location may interfere with functioning of lining and ability of the embryo to implant.

Classification Submucosal Fibroids Intramural Fibroids (most common) Subserosal Fibroids Pedunculated Fibroids Extrauterine Fibroids

Submucosal Fibroids Leiomyomata that are primarily on the endometrial side of

the uterus and protrude into the uterine cavity In muscle beneath the endometrium of the uterus Distorts uterine cavity Small lesion which may lead to bleeding and infertility Can prolapse through cervix, leading to labor-like uterine

contractions

Intramural Fibroids Leiomyomata that are primarily located in the uterine muscle It is the most common type They begin as small nodules in the muscular wall of the

uterus They may expand inwards and cause distortions and

elongation of the uterine cavity

Subserosal Fibroids Leiomyomata that are primarily on the outside of the uterus,

on the serosal surface. They are located underneath the mucosal surface of the

uterus They can become very large They can grow out into a papillary manner to become

pedunculated growths They can detach from the uterus and become parasitic

leiomyomata

Pedunculated Fibroids They are intra-cavitary fibroids located on the stalk They can be passed through the cervix

Extrauterine Fibroids Parasitic myomas They are located in other parts of the body Related or identical to metastasizing leiomyoma

Carneous Degeneration These are changes of the leiomyomata due to rapid growth The center of the fibroid becomes red, causing pain It is synonymous with red degeneration

Etiology

Exact mechanism is unknown Evidence suggest that uterine fibroid grows from a single mutated uterine smooth

muscle cell, and are thereby monoclonal tumors.

GENETIC

Chromosomal rearrangement. translocations between chromosomes 12 and14. Deletions of chromosome 7 Trisomy of chromosome 12 in large tumors. 60% may have yet undetected mutations More than 100 genes are up and down regulation in fibroid cells

internatinal Journal of Cancer

International Journal of Cancer

Diagnosis Pelvic examination: irregular pelvic mass that is mobile,

midline and moves contiguously with the cervix Transabdominal Ultrasound Transvaginal Ultrasound MRI Sonohysterography (Gynecologic ultrasonography)

Sonography is the most readily available and least costly to differentiate fibroids from other pelvic pathology . It is reasonably reliable for evaluation of uterus with< 375 cc volume and 3-4 or fewer fibroids.

Differential Diagnosis Adenomyosis Endometrial polyp Pregnancy Endometrial carcinoma

Treatment Many uterine fibroids are asymptomatic and only need to be monitored. Very rarely uterine leiomyomata degenerate into leiomyosarcoma Medication to control symptoms (like pain) such as NSAIDs Medications to shrink tumors: GnRH agonists such as Danazol but often

once you stop the treatment the tumors regrow to pretreatment size Thus GnRH agonist therapy is reserved for tumor shrinkage or correction

of anemia prior to operative treatment. Hysterectomy: for symptomatic fibroids when future pregnancy is

undesired. Ultrasound fibroid destruction Myomectomy for women who still desire children Uterine artery embolization

Uterine Artery Embolization Technique performed under anesthesia by cannulizing the

femoral artery and catheterizing both uterine arteries directly Infusing embolization particles that preferentially float to the

fibroid vessels This causes fibroid infarction and subsequent hyalinization and

fibrosis Initial studies with follow-up over 5 years shows symptom relief

for approx. 75% of women However this intervention should not be used in women who

want to get pregnant in the future because there is an increased risk of placentation abnormalities.

You don’t want these eggs that I made you? Fine. That’s fine. You know what?

That’s just GREAT. These perfectly good eggs. That I spent all month slaving over. It’s fine. I’ll just throw

them away. Whatever. No big deal.”