Intraoperative evaluation of myometrial invasion and histological type and grade in endometrial cancer: diagnostic value of frozen section.

PURPOSE: We have conducted a retrospective, comparative analysis of the accuracy of preoperative diagnosis and frozen section diagnosis relative to postoperative diagnosis.

METHODS

Subjects consisted of 168 patients with endometrial cancer, and frozen section was also performed. The diagnostic accuracy and the under-diagnosis rates in regard to both the myometrial invasion (MI) and the histological type and grade (HTG) were determined.

RESULTS

The diagnostic accuracy rate for preoperative HTG and MI were 64.3 and 54.8%, while the under-diagnosis rate was 25.0 and 35.7%. In contrast, the corresponding diagnostic accuracy rate for frozen HTG and MI were 84.5 and 85.7%, while under-diagnosis was 9.5 and 9.5%. Statistical analysis showed that the diagnostic accuracy rate for HTG and MI were significantly higher with frozen section diagnosis than with preoperative diagnosis (P<0.0001) and the under-diagnosis rate for HTG and MI were significantly lower with frozen section diagnosis than with preoperative diagnosis (P<0.0001).

CONCLUSIONS

Frozen section diagnosis was clearly more effective than preoperative diagnosis involving MRI as a basis for deciding the operative technique for endometrial cancer.