Ectopic endometrium in human foetuses is a common event and sustains the theory of müllerianosis in the pathogenesis of endometriosis, a disease that predisposes to cancer.
BACKGROUND
Endometriosis is a gynecological disease defined by the histological presence of endometrial glands and stroma outside the uterine cavity. Women with endometriosis have an increased risk of different types of malignancies, especially ovarian cancer and non-Hodgkin's lymphoma. Though there are several theories, researchers remain unsure as to the definitive cause of endometriosis. Our objective was to test the validity of the theory of müllerianosis for endometriosis, that is the misplacing of primitive endometrial tissue along the migratory pathway of foetal organogenesis


METHODS
We have collected at autopsy 36 human female foetuses at different gestational age. We have performed a morphological and immunohistochemical study (expression of oestrogen receptor and CA125) on the pelvic organs of the 36 foetuses included en-block and totally analyzed.


RESULTS
In 4 out of 36 foetuses we found presence of misplaced endometrium in five different ectopic sites: in the recto-vaginal septum, in the proximity of the Douglas pouch, in the mesenchimal tissue close to the posterior wall of the uterus, in the rectal tube at the level of muscularis propria, and in the wall of the uterus. All these sites are common location of endometriosis in women.


CONCLUSIONS
We propose that a cause of endometriosis is the dislocation of primitive endometrial tissue outside the uterine cavity during organogenesis.
Fondazione Italiana Endometriosi, Rome, Italy. aie@endometriosi.it
Pietro G
PG
Signorile
Feliciano
F
Baldi
Rossana
R
Bussani
Mariarosaria
M
D'Armiento
Maria
M
De Falco
Alfonso
A
Baldi
D016889:Endometrial Neoplasms / Q000209:etiology / Q000473:pathology*; D004715:Endometriosis / Q000150:complications / Q000473:pathology*; D005260:Female; D006801:Humans