Objective: The objective of the study was to determine the diagnostic accuracy of saline infusion ultrasonography (SIUS) compared to transvaginal ultrasonography (TVUS) in the assessment of myometrial invasion of endometrial cancer.
Methods: A total of 53 endometrial cancer patients were examined preoperatively with TVUS and SIUS with respect of myometrial invasion. All patients were postmenopausal. Ultrasonographic findings were compared to the histopathology of the surgical specimen.
Results: The median age of the patients was 64 ± 7 years (range 51 to 77 years). In all patients the procedure was well tolerated. The median thickness of malignant endometrium was 17 ± 9 mm (range 2 to 51 mm). The specimens consisted of 40 endometrioid adenocarcinomas, 2 serous papillary carcinomas, 5 clear cell carcinomas, 2 adenosquamous carcinomas, 3 mixed and 1 undifferentiated carcinoma. There were 18 G1, 24 G2 and 11 G3 cases. On histopathology, superficial myometrial invasion (≤ 50% of myometrium) was present in 25 (47.2%), and deep myometrial invasion (> 50% of myometrium) in 28 (52.8%) specimens. Superficial myometrial invasion, evaluated by TVUS, was accurate in 19 of 25 cases (76.0%) and by SIUS in 18 of 25 cases (72.0%). Deep myometrial invasion, evaluated by TVUS, was accurate in 24 of 28 cases (85.7%) and by SIUS in 27 of 28 cases (96.4%).
Conclusions: Transvaginal ultrasonography is a reliable method for assessing myometrial invasion of endometrial cancer. SIUS displayed slightly better accuracy in the assessment of myometrial invasion than TVUS, but the differences were not statistically significant.