Endometriosis Then and Now: A 100-Year Journey Around Pathogenesis and Clinicopathologic Associations.

CONTEXT.—: Nearly a century has passed since a seminal review article was published in 1928 in Archives of Pathology on ectopic endometriosis, presenting the dominant pathogenetic theories of the era: the serosal theory suggesting that endometriosis would arise by metaplasia of the peritoneal mesothelium; the metastatic theory implying the role of uterine lymphovascular invasion by endometrial tissue; and the implantation theory. Since then endometriosis has been the subject of numerous studies due to the associated morbidity and its significant impact on patients' quality of life and health care costs.

OBJECTIVE.—: To provide an overview of our evolving understanding of pathogenesis and clinicopathologic features of endometriosis.

DATA SOURCES.—: Review of the literature and personal experience of the authors.

CONCLUSIONS.—: The prevailing pathogenetic theory of endometriosis remains the retrograde menstruation and implantation theory proposed by Sampson in the 1920s. Contemporary studies have focused on the additional role of inherited genetic components, a supportive microenvironment, and molecular genetic alterations to improve the clinical classification, prognostication, and therapeutic options for patients with endometriosis.