Endometrial carcinoma: MR staging and causes of error

Purpose. This study was undertaken to prospectively determine the diagnostic capabilities of magnetic resonance (MR) imaging in detecting myometrialand cervical invasion and lymph node involvement in endometrial carcinoma and to identify the causes of errorsin staging endometrial carcinoma.Materials and methods. Twenty consecutive patients with a histological diagnosis of endometrial carcinomaunderwent preoperative MR imaging. MR findings were compared with surgical staging, considered as the standard of reference.Results. In assessing myometrial invasion, MR imaging showed 70% accuracy, 80% sensitivity, 40% specificity, 80% positive predictive value (PPV), and 40% negativepredictive value (NPV). In detecting cervical invasion, MR imaging had 95% accuracy, 100% sensitivity, 94.4%specificity, 66.7% PPV, and 100% NPV. In evaluating lymph node involvement, MR imaging showed 100% accuracy, sensitivity, specificity, PPV and NPV. Errors in evaluating myometrial invasion were caused by polypoidtumour, adenomyosis and leiomyomas, whereas those inevaluating cervical invasion were caused by dilatation and curettage.Conclusions. MR imaging is a reliable technique for preoperative evaluation of endometrial carcinoma. Itsmain limitation is differentiating between stage IA and IB carcinomas, which is not highly important for surgical planning. Cooperation between the gynaecologist andradiologist is mandatory to avoid staging errors.