Thin endometrial echo complex on ultrasound does not reliably exclude type 2 endometrial cancers.

OBJECTIVE: The objective of this study was to determine the ultrasonographic characteristics of the uterus and endometrial echo-complex (EEC) of postmenopausal patients diagnosed with type 2 endometrial cancer, including uterine papillary serous carcinoma (UPSC), clear cell carcinoma (CCC), and other endometrial high-grade carcinomas (HGC).

METHODS: Postmenopausal patients with type 2 endometrial cancer who underwent preoperative pelvic ultrasound were identified. Histologic diagnoses were made by biopsy or hysterectomy. Ultrasound reports were abstracted for the following parameters: EEC thickness, presence of intracavitary fluid or lesion, myometrial mass, uterine size, and adnexal mass. Ultrasound films were re-reviewed by a single gynecologic ultrasonographer.

RESULTS: Fifty-two patients with detailed ultrasound reports comprised the study population. Twenty-six films were available for re-review and inter-examiner agreement was 92%. Forty-four women (85%) presented with abnormal vaginal bleeding. Thirty-four patients (65%) had a thickened EEC measuring >5 mm. In 9 cases (17%), the EEC measured <4 mm. In an additional 9 patients (17%) the EEC was indistinct. One or more other ultrasound abnormalities were found in each of the 18 cases with a non-thickened EEC: intracavitary fluid or lesion (8; 44%), myometrial mass (12; 67%), enlarged uterus (13; 72%), or adnexal mass (5; 28%).

CONCLUSION: A thin or indistinct endometrial stripe, especially when associated with other ultrasound abnormalities does not reliably exclude type 2 endometrial cancer. Postmenopausal vaginal bleeding requires endometrial sampling despite a thin EEC in the presence of other ultrasonographic abnormalities or persistent bleeding.