Etiology

Begins with uninterrupted endometrial proliferation, progressing through states of simple to complex forms of endometrial hyperplasia (EH).
It begins as preinvasive intraepithelial lesions, which progress to full-blown invasive cancers involving endometrial stroma, then penetrating ever more deeply into the
myometrium to engage lymphatic capillaries that carry the malignancy to regional lymph nodes, whence metastases may occur through vascular channels.