Preinvasive endometrial proliferative disorders

Endometrial proliferative disorders include a large group of preinvasive lesions ranging from minimal or absent to high malignant potential. Because there is not a reproducible objective appraisal of their risk to invasive malignancy yet, any classification is based on subjective histopathological evaluation. The final objective of the evaluation of these lesions is to determine which ones have potential for spontaneous regression, which ones are amenable to medical treatment as definitive therapy, and which ones have malignant potential and require surgical intervention. Most of these lesions are estrogen-dependent, and removal of the offending cause and/or progestational therapy will result in regression. Non-estrogen or less-estrogen dependent lesions have a higher potential for persistence and progression to invasive malignancy, and require aggressive medical or surgical therapy. Endometrial intraepithelial carcinoma is a truly malignant process which may be associated with early metastatic dissemination even in the absence of myometrial invasion, and therefore surgical therapy is the only effective treatment. This review presents current concepts in the diagnosis and treatment of these lesions.