Preliminary Study of Endometrial Hyperplasia Groundwork for a Study to Define Precursors of Endometrial Cancer

This study, conducted jointly by the National Cancer Institute and the Kaiser Permanente Center for Health Research Northwest (KPCHRN) in Portland, Oregon, will lay the groundwork for a future study to identify precursors of endometrial cancer; that is, conditions that precede development of cancer of the lining of the uterus. The diagnosis of endometrial hyperplasia (a condition of abnormal proliferation of endometrial tissue) includes most precursors of endometrial cancer, as well as many benign conditions. Currently, three methods of classifying endometrial cancer precursors have been suggested based on endometrial hyperplasia findings, but it is not known which classification best predicts cancer risk. This study will examine surgical specimens of hyperplasia and cancer from women diagnosed with endometrial cancer at least 2 years after a diagnosis of endometrial hyperplasia. Investigators will estimate the percentage of cases with different degrees of hyperplasia, and assess the subsequent cancers that developed. This will allow them to rank hyperplasia lesions according to cancer risk and identify lesions that represent the most immediate cancer precursors. They will also review patients medical charts for information related to cancer risk and treatment. Study participants will include women enrolled in the KPCHRN who are 40 years of age or older and who were diagnosed with endometrial cancer at least 2 years after being diagnosed with endometrial hyperplasia.