Endometrioid adenocarcinoma arising in adenomyosis in a patient with pelvic organ prolapse—case report

BACKGROUND: Adenomyosis is a frequent finding in endometrial carcinoma patients. Endometrioid adenocarcinoma is the most common type of endometrial carcinoma; however, endometrioid adenocarcinoma arising from adenomyosis is extremely rare. CASE PRESENTATION: In this case report, we describe a 69-year-old woman who required surgical treatment for pelvic organ prolapse (POP). The patient had been postmenopausal for 20 years and had no abnormal bleeding after menopause. The patient underwent transvaginal hysterectomy, repair of anterior and posterior vaginal walls, ischium fascial fixation and repair of an old perineal laceration. Histological examination of surgical specimens revealed endometrioid adenocarcinoma of the uterus. Bilateral adnexectomy, pelvic lymphadenectomy and para-aortic lymphadenectomy were then performed. The postoperative histopathological diagnosis was stage IB endometrial cancer (endometrioid carcinoma G2). CONCLUSIONS: In summary, endometrioid adenocarcinoma arising from adenomyosis (EC-AIA) is a rare entity and the early diagnosis is difficult. Adequate preoperative assessment and enhanced inquiry of occult clinical symptoms of postmenopausal women before hysterectomy may contribute to the diagnosis of EC-AIA preoperatively.