Clinical Analysis Of Extrauterine Endometrial Stromal Sarcoma And Its Relationship With Coexisting Endometriosis

BackgroundEndometriosis is a benign disease histologically which may present malignant biological features such as local infiltration and metastasis. Moreover, endometriosis can undergo malignant transformation into malignant tumors of different pathological types, of which the most common types are adenocarcinoma (70%) and sarcoma (12%). For Higashiua’s perspectives, endometriosis associated malignant tumors are divided into the following several types:1) ovarian epithelial carcinoma, such as ovarian clear cell carcinoma and ovarian endometriod carcinoma;2) other mullerian tumors;3) sarcoma, such as endometrial stromal sarcoma and adenosarcoma. Mostly, ESS occurs from uterus. However, ESS arising in extrauterine site in the absence of uterine involvement does exist. There are at least two hypotheses to explain the origin of extra-uterine ESS. One explanation is the malignant transformation of endometriosis. Several reports have been established. The other is that it potentially derives from Mullerian cells. To study the clinical features of extrauterine endometrial stromal sarcomaand its relationship with endometriosis, it will enhance our understanding of malignant transformation of endometriosis and the origin of extrauterine endometrial stromal sarcoma.ObjecyivesTo explore the clinical and pathological features of extrauterine endometrial stromal sarcoma and the relationship with coexisting endometriosis.Study designThe medical records of86patients with endometrial stromal sarcoma receiving surgery at Peking Union Medical College Hospital from December2002to December2012were reviewed. Pathologically diagnosed uterine-derived endometrial stromal sarcoma (n=75), and extra-uterine endometrial stromal sarcoma (n=11). Among those11patents,4were with coexisting endometriosis.ResultsCompared with uterine-derived endometrial stromal sarcoma, patients with extra-uterine endometrial stromal sarcoma were proved:(1) to be with different manifestations, pelvic mass dominating (45.5%, P=0.010);(2) to have similar presurgical CA125level;(3) to be diagnosed at later stage (P<.001);(4) to be more likely with coexisting endometriosis (36.4%vs9.3%, P=0.031);(5) to show no difference in pathologic subtypes distribution and immunohistochemical staining features.ConclusionsCompared with uterine-derived endometrial stromal sarcoma, extra-uterine endometrial stromal sarcoma has different clinical features and might be closely relavent to endometriosis.