Sorting Out Hyperplasia

Page 2 - Types of Hyperplasia

The most current research indicates that two key factors are the most meaningful: 1) whether the hyperplasia is “simple” or “complex,” and 2) whether “atypical cells” (also called “atypia”) are present in the endometrium.  Atypia can be present in either simple or complex hyperplasia, so there are four basic types in all.

In simple hyperplasia without atypia, there is proliferation of cells, but the basic structure of the endometrium is relatively unchanged.  This is considered to be the least dangerous type of hyperplasia.  Other terms that are approximately the same as simple hyperplasia are mild, cystic, or Swiss-cheese hyperplasia.

In complex hyperplasia without atypia, the individual cells may be enlarged, but, as in simple hyperplasia, the internal makeup of the cells is considered to be normal.  However, the cells have proliferated to the point where the normal structure of the endometrium is interfered with.   Glands crowd each other, and under a microscope the architecture is jumbled and less regular.  Other descriptors in this general category are adenomatous, moderate, or glandular hyperplasia.  (Side note: I found references to “glandular” hyperplasia along with cystic or mild hyperplasia as well.)

If atypia is NOT present, these two types of hyperplasia, taken together, have been found to have a 1-4% chance of becoming endometrial cancer.  Now, whenever you see a statistic like this, you should then ask, “what are the chances of getting endometrial cancer in any case?  What are the chances of any random woman getting endometrial cancer?”  The answer to that question is “about 3%”.  Therefore, these types of hyperplasia are now NOT generally considered to be precancerous.  Most of the time, they respond to progestin therapy, which causes the endometrium (and the problem) to be sloughed off as it would be during a normal period.   It turns out that Jana, one of the friends I talked about at the beginning of the article, is in this group.  Additionally, she is in perimenopause, which means that there is a very good chance that menopause will solve the problem altogether.

What does it mean when atypical cells are present?  Atypia means that the cells themselves have become abnormal.  This is a similar case to cervical dysplasia.  Although these cells are not cancerous, there is an increased probability that they will become so.  We can think of them of "going towards" cancer, but not yet "arrived".

Remembering that atypia also can be divided into simple and complex, simple hyperplasia with atypia would be next on the list.  This less common type of hyperplasia often responds to progestin therapy.  It has an 8% chance of progressing to cancer.

 This leaves complex hyperplasia with atypia, which is the one to look out for.  Approximately 25-30% of hyperplasia in this category will progress to endometrial cancer.  For this reason, the suggested treatment for atypical complex hyperplasia is usually hysterectomy.  However, if you are interested in preserving your uterus, you should know that even this category is on a continuum from mild to severe. Mild complex hyperplasia with atypia often responds to progestin therapy, so if this is your case, then you might want to inquire about this option.  However, the more severe the atypia, the less chance it will reverse itself with hormone therapy.  In one study, only 20% of the cases of severe atypia responded to progestin, and fairly often (25-45% of the time) when hysterectomies are performed on these patients, previously undetected endometrial cancer is found.  Of course, all decisions about treatment in an individual case would be made in conjunction with a physician.  My friend Connie does have complex atypical hyperplasia.  She is 64, and is taking hormone replacement therapy.  Because of her higher risk for endometrial cancer, she will be having a hysterectomy.

Even when hyperplasia does lead to cancer, there is good news, which is that endometrial cancer is slow to grow and spread, and almost always shows itself early as non-menstrual bleeding, which is also the chief symptom of hyperplasia.  If women are alert to this symptom, most endometrial cancer and pre-cancer can be eliminated before it becomes life-threatening.

For more information:

Q&A's Pertinent to Endometrial Hyperplasia

Photograph of endometrial hyperplasia from the University of Utah

PDQ File on Prevention of Endometrial Cancer from the National Cancer Institute

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