What is characterized as an abnormal growth of endometrial cells with potential for cancer progression?

Endometrial hyperplasia is characterized by an abnormal proliferation of the endometrial lining, which can occur in response to excess estrogen without adequate progesterone. This condition involves an increase in the number of endometrial glands relative to the stroma, leading to thickening of the endometrial tissue. While not cancer itself, endometrial hyperplasia is a precursor lesion and carries a risk of progression to endometrial carcinoma, particularly in cases of atypical hyperplasia. Understanding this connection is crucial for identifying and managing patients at risk for developing more severe forms of endometrial pathology.

In contrast, endometrial carcinoma is already a cancerous growth of endometrial cells, representing a more advanced state of abnormal cell proliferation. Endometrial atrophy refers to a thinning of the endometrial lining, typically associated with decreased estrogen levels, and does not carry a risk of cancer. Endometriosis involves the presence of endometrial-like tissue outside the uterus, causing various symptoms, but it is not characterized by a malignant transformation of endometrial cells. Therefore, endometrial hyperplasia is the correct answer due to its initial stage of abnormal growth and its potential link to cancer.