Preoperative staging of endometrial cancer using TVS, MRI, and hysteroscopy.

OBJECTIVES: To evaluate the accuracy of different preoperative modalities for staging of endometrial cancer to restrict extensive surgery to patients at high risk of metastatic disease.
SETTING: Aarhus University Hospital. POPULATION: 156 women referred in 2006-2011 because of atypical endometrial hyperplasia (G0) or endometrial cancer.
METHODS: Patients were offered preoperative transvaginal ultrasonography (TVS), magnetic resonance imaging (MRI), and hysteroscopic-directed biopsies from the uterine tumor and cervix. Final pathology of the removed uterus was the reference standard. Patients were divided into low risk (<50% myometrial invasion, and grades 0, 1, 2, and no cervical invasion) or high risk (all others). MAIN OUTCOME MEASURES: Accuracy, sensitivity, specificity, positive/negative predictive value.
RESULTS: Patients were aged 32-88 years, with a mean body mass index of 29. At final pathology 81% had cancer and 19% G0 or no residual tumor; 54% were high risk. Hysteroscopy-directed biopsies had a higher accuracy (92%) than endometrial biopsy (58%) for differentiating G0 from cancer (p < 0.001); grade 3 tumor identification had similar accuracy (93 vs. 92%). Deep myometrial invasion was estimated with higher accuracy by MRI (82%) than TVS (74%) (p < 0.02). For cervical involvement, hysteroscopy-directed biopsies had higher accuracy (94%) than MRI (84%,) and TVS (80%) (p < 0.02). Accuracy for identifying high-risk women was highest (83%) using a combination of MRI and hysteroscopic-directed biopsies, compared with TVS and endometrial biopsy (72%) (p < 0.05).
CONCLUSION: Preoperative staging with MRI and hysteroscopy-directed biopsy can identify eight of 10 women with high risk of lymph node metastases and spare eight of 10 low-risk women extended surgery.