Preoperative local-regional staging of endometrial cancer: transvaginal sonography versus magnetic resonance imaging

Objectives: The aim of this study was to compare the accuracy of transvaginal sonography (TVS) and magnetic resonance imaging (MRI) in the preoperative staging of endometrial carcinoma. Methods: Some 74 consecutive women diagnosed as having endometrial carcinoma were prospectively evaluated at TVS by physicians trained in gynecological sonography and at MRI by radiologists with a special interest in gynecology. All patients underwent surgical/pathological staging after removal of the uterus, adnexa and pelvic lymph nodes. Sensitivity, specificity, positive and negative predictive values were calculated for both imaging modalities as regards neoplastic invasion of the outer half of the myometrium and cervical involvement. Results: TVS and MRI performed equally well in the preoperative staging of endometrial cancer, with no statistical differences. Sensitivity, specificity, positive and negative predictive values and overall diagnostic accuracy for TVS in the evaluation of myometrial infiltration were 79%, 87%, 84%, 83% and 84%. Values for MRI were respectively 77%, 87%, 84%, 81% and 81%. Corresponding features for detection of cervical involvement were 72%, 98%, 93%, 92% and 92% for TVS, and 58%, 94%, 79%, 87% and 85% for MRI. Conclusions: In expert hands, TVS shows a good accuracy in local regional staging of endometrial carcinoma. Owing to its high costs, MRI should be offered only to those cases in which TVS gives images of poor quality.