Is routine frozen section analysis necessary in patients with non‐endometrioid cancer or grade 3 endometrioid cancer?

OBJECTIVE: To explore the accuracy related to type and subtype between frozen section (FS) results and final pathology results in patients with endometrial cancer and to suggest whether it should be routinely performed. METHODS: Retrospective data were collected from 184 patients with endometrial cancer who underwent surgery at a single center (January 2014–December 2018). FS results were compared with the final pathology results with respect to histotype, tumor grade, and depth of invasion to define the accuracy of FS analysis. RESULTS: Frozen section analysis was performed in 141 (76.6%) patients. The accuracy rates and κ values between the FS and final pathology results with respect to histotype, tumor grade, and depth of invasion were 87.23%, 81.15%, and 98.2% and 0.41, 0.7, and 0.9, respectively (P < 0.001). Among the 18 patients with preoperative non‐endometrioid cancer (non‐EC), six underwent FS analysis, and final pathology confirmed EC in three, of whom 75% were detected by FS analysis. Eight of 19 patients with preoperative grade 3 EC underwent FS analysis and the accuracy rate was 87.5%. CONCLUSION: Intraoperative FS analysis is a reliable method that can help intraoperative decision making. It should be performed routinely in patients with non‐EC and grade 3 EC.