Challenges to Intraoperative Evaluation of Endometrial Cancer

Abstract

Background and objectives: Intraoperative evaluation of the uterus has been reported to predict risk of lymph node spread in endometrial cancer. Four criteria have been prospectively validated by the Mayo Clinic; histopathology, grade, tumor size, and depth of myometrial invasion. The objective of this study is to assess the accuracy of intraoperative evaluation in a university-affiliated teaching setting.

Methods: This study was a retrospective chart review of 105 cases of endometrial cancer who underwent robotic-assisted staging from January 2016 through December 2017.

Results: Seventy-five cases were included. The mean age was 65 y and mean body mass index was 33 kg/m². Fifty-eight patients (80.6%) had no change between intraoperative and postoperative grade. This yielded a 19.4% discordance rate with a significant disagreement (P = .003, Cohen's κ = 0.705). Fifty-eight patients (82.9%) had no change in depth of invasion. This yielded a 17.1% discordance rate with a significant disagreement (P = .0498, Cohen's kappa of 0.69 [95% confidence interval, 0.53-0.85]). Average tumor diameter was 3.4 cm. Seven patients (11.7%) were upsized from the low-risk (≤2 cm) to the high-risk category (>2 cm). This led to an 11.7% discordance rate, with a significant disagreement (P = .008, Cohen's kappa of 0.69 [95% confidence interval, 0.48-0.89]). In 15 of 75 cases (20%), intraoperative evaluation of the size of the tumor was not possible and deferred to the final pathology report.

Conclusion: We conclude the Mayo Clinic Criteria cannot be universally adopted until all four criteria can be validated through a prospective study that includes institutions that have variable resources.

Keywords: endometrial cancer; frozen section; lymph node dissection; staging.