ABSTRACT
Obiective To explore the risk factors of endometriosis-associated ovarian cancer (EAOC) in women with ovarian endometriosis aged 45 years and older in China. Methods The medical records of total 1038 women aged 45 years and older with a surgicopathological diagnosis of ovarian endometriosis treated at Peking Union Medical College Hospital from December 1994 to December 2014 were reviewed. Histology evaluation determined ovarian endometriosis with (n=30) or without (n=1008) ovarian cancer. Results (1) There were 30 (2.9%, 30/1018) cases confirmed as having EAOC. Clear cell carcinoma (63.3%, 17/30) and endometrioid adenocarcinoma (23.3%, 7/30) were commonly observed subtypes and 70.0%of EAOC patients were at stageⅠ. (2) Compared women with ovarian endometriosis in the same age group,patients with EAOC were older (50.8 vs 48.5 years, P=0.002). There were more in postmenopausal status at diagnosis of EAOC (P＜0.01). There were more found with a mass ≥8 cm (P＜0.01). Women with EAOC had higher prevalence of coexisting endometrial disorders (P=0.003). No differences were found in preoperative CA125 value and infertile or nulliparous women (P＞0.05). Conclusions For women with ovarian endometriosis aged 45 years and older, the subgroup of patients characterized by postmenopausal status and ovarian endometrioma (≥8 cm) have a higher risk of EAOC. Active intervention or intensive follow-up should be considered for this population group, especially for those concurrent with endometrial disorders.