Endometrial cancer: results of clinical and histopathological staging compared to magnetic resonance imaging using an endorectal surface coil.

Purpose: The aim of this study was to evaluate the staging accuracy of magnetic resonance imaging (MRI) with an endorectal surface coil on patients with endometrial cancer compared to results obtained using the International Federation of Gynecology and Obstetrics (FIGO) classification and histopathology.

Methods: In this prospective study, patients with biopsy-proven endometrial cancer were staged clinically using the FIGO classification before undergoing 1.5 T MRI with an endorectal surface coil (eMRI). The staging results from the FIGO classification and from eMRI were compared with the histopathological results after surgery. Furthermore, each patient was given a questionnaire designed by the authors to evaluate the patients' opinions on eMRI. The responses were examined using the methods of descriptive analysis.

Results: A total of 33 consecutive patients were recruited and clinically staged before undergoing eMRI. Subsequently, 21 patients underwent primary surgery and 12 patients primary radiochemotherapy. The FIGO stages were identical to the histopathological results in 17 (81 %) cases, and those of eMRI were identical in 15 (71 %). In 13 (62 %) cases, FIGO and eMRI staged identically. In 12 (57 %) of the 21 cases, all three staging modalities diagnosed the same tumor stage. eMRI overstaged the tumor in four patients and understaged it in two. All T1a tumors were staged correctly by eMRI. Eighteen patients answered the questionnaire, of whom 11 (61 %) patients stated that their experience with eMRI was overall positive.

Conclusions: It seems feasible in principle to employ eMRI for diagnosing patients with endometrial cancer stage T1a. Yet, the results of eMRI for our study population were not better than the results obtained using the FIGO classification or than those from using MRI without an endorectal surface coil. eMRI thus does not meet the expectations based on its use in other pelvic tumor entities.