Adenomyosis.

Abstract

Adenomyosis has been defined as the “benign invasion of endometrium into the myometrium, producing a diffusely enlarged uterus which microscopically exhibits ectopic nonneoplastic endometrial glands and stroma surrounded by a hypertrophic (increase in the volume of an organ or tissue due to the enlargement of its component cells) and hyperplastic (increase in the amount of organic tissue that results from cell proliferation) myometrium”. Two separate pathogenetic theories have been advanced to explain its formation: (1) an origin from the invagination of the deepest portion of the endometrial mucosa between bundles of smooth muscle fibres of the myometrium, or along the intramyometrial lymphatic system; (2) a metaplastic process initiating from ectopic intramyometrial endometrial tissue produced de novo.