Menopause and Endometriosis - Symptoms and Risk of Malignant Transformation: A Systematic Review of the Literature

To review the evidence concerning the clinical presentation of endometriosis in postmenopausal women and the associated risk of malignant transformation.

This systematic review was conducted following the PRISMA 2020 guidelines and prospectively registered with PROSPERO (CRD420251025035). The study research was conducted across three databases: MEDLINE/PubMed, Scopus, and the Cochrane Library. Only studies published in English were considered, and publications prior to 2000 were excluded from the review.

Two authors independently screened all records. Studies were selected if they included postmenopausal women with endometriosis and reported data on clinical symptoms or malignant transformation of endometriotic lesions. We included 32 articles, comprising case-control studies, cohort studies, case series, and cross-sectional studies, encompassing 30 895 women with histologically confirmed endometriosis.

Six studies provided information on the clinical manifestations, with 55.7% of women experiencing no symptoms. Among symptomatic women, pelvic or abdominal pain was the most common. Malignant transformation of endometrioma into ovarian cancer was reported in 29 articles, with 821 ovarian cancer cases identified. Ovarian clear cell carcinoma (OCCC) and ovarian endometrioid carcinoma (OEC) were the most common histological subtypes related to endometriosis. Risk of bias was assessed using the Newcastle-Ottawa Scale (NOS) and the Joanna Briggs Institute (JBI) Critical Appraisal Tools.

Most postmenopausal women with endometriosis are asymptomatic; however, a small subset may have ectopic implants that remain biologically active and progress to malignant precursor forms. Postmenopausal endometriosis appears to confer an increased risk of ovarian carcinoma, particularly OCCC and OEC. Therefore, clinicians should consider this diagnosis and ensure an appropriate assessment for malignancy.