Endometrial Hyperplasia
Endometrial hyperplasia is a disease of the endometrium whereby there are structural changes in the glands and stroma of the mucosal layer of the uterus – endometrium. Moreover, there is always an absolute or a relative increase in the level of estrogen in the blood (hyperestrogenia). It can develop at any age – at 17 years old, 60, or more.
Endometrium in normal form is composed of glands and stroma (bed). Depending on which tissue is growing, endometrial hyperplasia can be of the following basic types:
- glandular endometrial hyperplasia
- cystic glandular endometrial hyperplasia
- fibrous endometrial hyperplasia
- atypical endometrial hyperplasia (focal and diffuse forms
There is a more modern classification, which divides endometrial hyperplasia into simple and complex (with or without atypia).
Structural glandular endometrial hyperplasia and cystic glandular endometrial hyperplasia form are characterized by the presence of expanded cystically-changed glands. Glandular endometrial hyperplasia is one of the most common types of endometrial pathology. Atypical endometrial hyperplasia manifests itself in the form of abundantly overgrown glands and significant decrease in stromal elements.
Cystic glandular endometrial hyperplasia and atypical endometrial hyperplasia are background processes, leading to the development of endometrial cancer. The percentage of transformation to cancer in these processes range from 1 to 5% and 20 to 30% respectively. According to medical data (WHO classification), the risk of malignant processes amid atypical endometrial hyperplasia ranges from 15 to 40%.
The histological classification (1975) by WHO identifies three main types of hyperplastic processes in the endometrium: polyps, endometrial hyperplasia and atypical endometrial hyperplasia.
