ENDOMETRIAL CARCINOMA OF THE OVARY, ARISING IN ENDOMETRIAL TISSUE IN THAT ORGAN

Many interesting and important problems have presented themselves to clinicians and pathologists, who have appreciated the frequency of ectopic endometrium-like tissue in the pelvis and have had an opportunity to observe the various lesions in the ovaries and other pelvic structures resulting from this tissue. One of the most interesting problems is the source of these implantation-like lesions occurring on the surface of the various pelvic structures. Are they true implantations derived primarily from uterine or tubal epithelium escaping through the tubes into the peritoneal cavity, as the study of many of these lesions in human beings indicates¹ and as Jacobson,² in the autotransplantation of endometrial tissue in rabbits, has experimentally proved possible, or are they derived from scattered localized metaplasias of the serosal mesothelium or from developmental inclusions of portions of the Wolffian body or Müllerian duct? This problem has not yet been definitely solved to the