INTRODUCTIONEndometrial polyps are common in both menopausal and non-menopausal patients, often detected incidentally or presenting with abnormal uterine bleeding or infertility. While the malignancy risk is generally low, malignant transformation is possible. This paper highlights a case of malignant transformation in an endometrial polyp and reviews its diagnostic methods, treatment, and prognosis.CASE REPORTA 68-year-old postmenopausal woman presented with metrorrhagia. Clinical and imaging assessments revealed an endometrial polyp, confirmed via hysteroscopy. She underwent polypectomy, and histopathology identified a Grade 1 endometrioid adenocarcinoma arising from the polyp, classified as a POLE-mutated carcinoma. The POLE mutation was identified using molecular sequencing rather than immunohistochemistry. Further evaluations, including pelvic MRI and thoraco-abdominopelvic CT, showed no myometrial invasion or metastasis. Definitive management involved a total hysterectomy with bilateral salpingo-oophorectomy. Histological examination of the surgical specimen confirmed the diagnosis, and the patient remained disease-free during follow-up.DISCUSSIONEndometrial polyps are common localized intrauterine lesions influenced by estrogen and progesterone. Their prevalence varies widely, with higher rates in postmenopausal women and those with risk factors such as obesity, hypertension, and tamoxifen use. While most polyps are benign, the risk of malignancy ranges from 0.5 % to 5.4 %, increasing with age, menopausal status, and abnormal uterine bleeding. Recent studies in South Korea reported a 7.2 % prevalence of precancerous or malignant lesions, identifying menopause, abnormal bleeding, obesity, multiple polyps, and nulliparity as key risk factors. Meta-analyses confirm a malignancy rate of approximately 3 %, rising to 5 % in symptomatic or postmenopausal women. The presence of abnormal uterine bleeding in a postmenopausal patient should prompt histopathological examination of polyps, as demonstrated in this case.CONCLUSIONAbnormal uterine bleeding and menopause notably raise the risk of malignancy in endometrial polyps. Histological evaluation of resected polyps is crucial, even when clinical suspicion is low, as demonstrated by our case of adenocarcinoma identified in a polyp. Proper adherence to established guidelines for the management of postmenopausal bleeding and endometrial thickening remains essential.