[Impact of 2009 FIGO staging system on the diagnostic value of preoperative MRI staging of endometrial carcinoma]

Abstract

Objective: To analyze the changes of 2009 FIGO staging system compared with the 1988 FIGO staging system of endometrial carcinoma and evaluate the diagnostic value of MRI staging by the 2009 FIGO criteria.

Methods: A retrospective study was performed on 63 consecutive patients with pathologically confirmed endometrial carcinoma who were treated by surgery initially from January to December 2009. The diagnostic value of preoperative MRI by the 2009 FIGO staging system was compared with that using the 1988 FIGO system, respectively.

Results: According to the 2009 FIGO staging system of endometrial carcinoma, stage Ia was defined as no or less than half myometrial invasion, which included stage Ia (confined to endometrium) and stage Ib (invasion less than half of the myometrium) of the 1988 FIGO staging system. Stage Ib assessed by the 2009 FIGO system was the same as the stage Ic of 1988 FIGO system, indicating the lesions more than half myometrial invasion. Endocervical glandular involvement only (stage IIa of 1988 FIGO system) was classified as stage I. Positive cytology of ascites (stage IIIa of 1988 FIGO system) was excluded by the 2009 FIGO criteria. Using the 1988 FIGO system, the accuracy of MRI for the evaluation of endometrial carcinoma of stage Ia, Ib, Ic, whole stage I, IIa, IIb, whole stage II, IIIa, IIIb, IIIc, whole stage III and IVb were 95.2%, 79.4%, 81.0%, 84.1%, 96.8%, 90.5%, 90.5%, 92.1%, 98.4%, 92.1%, 82.5%, and 98.4%, respectively, while using the 2009 FIGO system, the accuracy of MRI of stage Ia, Ib, whole stage I, II, IIIa, IIIb, IIIc, whole stage III and IVb were 88.9%, 81.0%, 88.9%, 92.1%, 98.4%, 98.4%, 92.1%, 88.9% and 98.4%, respectively.

Conclusions: The 2009 FIGO staging system is simplified on the basis of the 1988 FIGO system. It gives an improved accuracy of MRI in evaluating the stage I to III endometrial carcinoma.