Endometrial Hyperplasia and Endometrial Cancer

If you have questions or need a physician referral, please contact HERS at 610-667-7757.

The inside lining of the uterus is called the endometrium. Because the endometrium builds up between menstrual cycles and then sheds during menstruation, the endometrium is thickest just before menstruation and thinnest just after menstruation ends. Endometrial hyperplasia is characterized by a thickening of the endometrium that is more than the typical pre and post-menstrual build up of endometrial tissue.

The symptom most frequently associated with endometrial hyperplasia is heavy, extremely long, or continuous bleeding without large blood clots. Large blood clots are typical of fibroids, but not with endometrial hyperplasia.

There are several factors that can predispose a woman to developing endometrial hyperplasia. The most common cause is taking exogenous hormones. Exogenous hormones are not produced in your body, they are taken as pills, applied as patches and creams, or given by injections.

Estrogen and progesterone are hormones produced in the ovaries that balance each other. An example of how they work together is in the regulation of menstruation. One of the functions of progesterone is to oppose estrogen, which causes the uterus to shed the endometrium during menstruation before a new cycle of proliferation, or building up, begins in preparation for the next menstruation.

Exogenous estrogen taken without progesterone will frequently cause hyperplasia. Exogenous estrogen taken in combination with progesterone may also cause hyperplasia, though it is likely to take longer to develop.

Excess estrogen is stored in fatty tissue. Excess androgen is converted to estrogen, and then stored in fatty tissue. So another factor is weight. Endometrial hyperplasia is much more common in women who are significantly overweight.

An endocrine-disrupting diet, such as one that includes large amounts of tofu, or the ingesting of endocrine-disrupting chemicals like bisphenol-A (BPA is present in many kinds of plastics), may also stimulate a production of excess estrogen that can lead to hyperplasia.

Because Polycystic Ovarian Syndrome (PCOS) is marked by elevated levels of androgens and difficulty maintaining weight, many women who have PCOS develop hyperplasia.

Hyperplasia often spontaneously reverts to normal, particularly if it occurs at a low level during the hormone changes associated with perimenopause (the beginning of menopause). If it does not revert to normal, hyperplasia may progress through a series of stages.

Perimenopausal hyperplasia often spontaneously reverts to normal within a few months after menstruation stops. When it does not revert to normal, the endometrium may continue to thicken and develop into complex hyperplasia or complex hyperplasia with atypia. If untreated, complex hyperplasia may develop into endometrial cancer.

Many doctors first perform an endometrial biopsy. An endometrial biopsy removes a small piece of endometrial tissue with a thin, glass, straw-like pipelle. It is a painful procedure that is inadequate in evaluating the endometrium for hyperplasia. It can only tell you what is going on in the one spot where the tiny piece of endometrial tissue was removed.

The first step in determining if you have hyperplasia is a pelvic and transvaginal ultrasound, which evaluates the thickness of the endometrium. The endometrium is thickest right before menstruation begins and thinnest right after it ends. So if an ultrasound is performed it should be completed within a day or two after menstruation stops– when the thickness of the endometrium is usually between 4mm and 7mm.

If a pelvic and transvaginal ultrasound reveals that the endometrium is abnormally thickened, it should be confirmed the following month with a repeat ultrasound. The repeat ultrasound should also be performed within a day or two after menstruation stops.

If the endometrium remains thickened or if bleeding is continuous for two months in a row, then a D&C will both diagnose and treat hyperplasia. D&C refers to dilation, opening the cervical canal, and curettage, scraping the endometrium with a sharp instrument called a curette. A gynecologist inserts a curette through the dilated cervix and into the uterus. The doctor will then scrape the endometrium and send the tissue to a pathologist for analysis and diagnosis. The D&C allows a pathologist to determine if hyperplasia exists. If hyperplasia is present, the D&C will help determine what level of hyperplasia was found and determine if further treatment is indicated.

Although ablation is contraindicated (not advised) for endometrial hyperplasia, it is nonetheless commonly recommended and performed to stop heavy bleeding. Ablation is a destructive surgery where the inside of the uterus is scarred by burning it with either heat or freezing.

Endometrial ablation is not a good treatment for hyperplasia because it may mask hyperplasia. Because ablation scars the inside of the uterus, it stops the normal growth and proliferation of the endometrium, so the endometrium cannot be evaluated to see if it is reverting to normal or if the hyperplasia is progressing. If hyperplasia continues to progress because it is not seen on an ultrasound and therefore is not being treated, what began as a low-level hyperplasia can progress to a higher level without being detected because the inside of the uterus has been scarred by ablation.

Many women continue to experience bleeding after endometrial ablation. The bleeding may be a result of damage to the uterus caused by the ablation, or the bleeding may continue because some areas of the endometrium may have been burned unevenly leaving it to grow and bleed. And because of the scarring, there is no way of knowing if the bleeding is caused by the ablation or by hyperplasia. At that point women are likely to be told the only solution is a hysterectomy, surgical removal of the uterus.

If you are not told about the risks of ablation and conservative treatment for hyperplasia, you cannot know what you are consenting to if you agree to endometrial ablation.

There are many types of endometrial ablation, including Rollerball (electrocautery), Thermal Balloon, Laser, Cryo (freezing), and Microwave, but the result of each method or technique is similar–it is a damaging surgery that scars the inside of the uterus, which can cause a host of problems that often lead to more invasive treatments, chronic pain, infection, hysterectomy, and sometimes death.

Unless you have taken hormones, which can cause it to grow faster, endometrial hyperplasia is slow growing. It takes ten to twelve years from the time it begins to grow for it to develop into endometrial cancer.

There are several stages of endometrial hyperplasia, starting with simple, then cystic, and on up the ladder until the last stage, complex hyperplasia with significant atypia that is poorly differentiated. The diagnosis can be made by a pathologist after a D&C.

An early level of hyperplasia usually responds to a small dosage of progesterone, such as Provera. A higher level of hyperplasia responds better to a stronger progesterone, such as Megace. With a higher level of hyperplasia, after three months of treatment with a high dose of Megace, a D&C should be repeated to make sure the tissue is returning to normal. Once the endometrium returns to normal, an ultrasound every six to eight months will show whether the endometrium is thick, and if a D&C is warranted.

Early endometrial cancer may respond to a high dose of Megace as well. More frequent monitoring with ultrasound and a D&C every six months for the first 12 to 18 months is important to monitor the endometrial thickness.

The uterus and ovaries have many important lifelong functions. The most consistent problems women report after hysterectomy include a 25-pound average weight gain in the first year following the surgery, a loss of sexual feeling, a loss of vitality, joint pain, back pain, profound fatigue, and personality change.

For more information, watch the short video “Female Anatomy: the Functions of the Female Organs.”


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