Guest Author - Dr. Denise Howard
Endometrial cancer results from malignant changes in a variety of different cell types within the uterus. Thus, endometrial cancer is not a single entity and therefore is likely to have a number of potential causes. There is still much more to be learned about this cancer, even though great strides have been made. It is the most commonly diagnosed cancer of the female reproductive tract and the one with the best prognosis since it typically presents early in its course.
Endometrial cancers can be grouped into 2 types. Approximately 80-85% are described as Type 1. They have endometriod histology and are described as grade 1 or 2. This means that they are not aggressive cancers. They usually result from excessive estrogen exposure and typically will present with precancerous changes before developing to a malignancy. The cancers are quite responsive to treatment and the chance of cure is quite high.
Type 2 endometrial cancers include serous, clear cell, mucinous, squamous, transitional cell and undifferentiated types as well as grade 3 endometriod. They are aggressive cancers, spreading rapidly and therefore have a poor prognosis. These tumors are often high grade with an unclear cause but do not appear to be related to estrogen exposure and there isnít any evidence of a precursor lesion, which would lend itself to early diagnosis.
Much of what is known about the epidemiology of endometrial cancer refers to the Type 1 cancers. A number of factors contribute to the development of cancer. These include exposure to chemicals or radiation, genetic predisposition but excessive estrogen exposure is the hallmark of Type 1 cancers.
Estrogen stimulates the lining of the uterus to grow, preparing for implantation of the fertilized egg. If pregnancy does not occur, a cascade of events are triggered which lead to a drop in estrogen level and then a withdrawal bleed which is menstruation. If a woman is not ovulating monthly then the lining of the uterus will continue to grow, as estrogen levels remain high. This continuous growth may result in abnormal changes, which could lead to the development of endometrial cancer. The growth results from the continuous presence of high estrogen levels.
Endometrial tissue that is exposed to continuous excessive estrogen undergoes a gradual transition from normal to abnormal. During this transition, the tissue has a typical appearance that allows the identification of precancerous changes. These precursor lesions are described as hyperplasia. The gradual transition has been described by grading the hyperplasia. Simple hyperplasia is the lowest level and complex is the highest. If there is evidence of atypical cell components then is can be described as with atypia. The presence of complex hyperplasia with atypia is the final step before cancer. If this is found on biopsy, there is a high chance that cancer may also be present. Surgical removal of the uterus can prevent the development of endometrial cancer if hyperplasia is discovered.
Most endometrial cancers are easily treated because they have an identifiable precursor lesion and have classic symptoms that should lead to early diagnosis. It is therefore important to recognize these symptoms and see your gynecologist as soon as possible for a through evaluation.
I hope this article has provided you with information that will help you make wise choices, so you may:
Live healthy, live well and live long!