Prognostic significance of gross myometrial invasion with endometrial cancer.

Objective: To determine if intraoperative estimation of gross myometrial invasion is sufficiently precise to guide surgical aggressiveness in staging patients with endometrial cancer.

Methods: Between September 1987 and September 1995, 236 women with endometrial cancer had visual estimation of gross myometrial invasion during surgical staging which included pelvic and para-aortic lymphadenectomy.

Results: In 213 patients (90.3%), the depth of gross myometrial invasion correctly predicted the microscopic depth of invasion on permanent histopathologic sections. Statistically significant associations were found between gross depth of myometrial invasion and tumor grade (P < .001), histopathology (P = .014), cervical metastases (P < .001), adnexal metastases (P < .001), omental metastases (P < .001), malignant pelvic cytology (P < .001), pelvic lymph node metastases (P < .001), para-aortic lymph node metastases (P = .001), and surgical stage (P < .001). Patients with more than 50% gross myometrial invasion were more likely to have poorly differentiated malignancies; nonendometrial histologies; malignant pelvic cytology; higher surgical stage; and cervical, adnexal, omental, pelvic lymph node, and para-aortic lymph node metastases. Patients with more than 50% gross myometrial invasion had a 6.4-fold higher prevalence of pelvic lymph node metastases, a 6.9-fold higher prevalence of para-aortic lymph node metastases, and a 6.7-fold higher prevalence of advanced surgical stage than patients with less than 50% myometrial invasion.

Conclusion: Patients with endometrial cancer and more than 50% myometrial invasion on gross visual intraoperative estimation are at marked risk for extrauterine metastases, including pelvic and para-aortic lymph node metastases. Such patients should be considered for more aggressive surgical staging, including pelvic and para-aortic lymphadenectomy.