Prognostic implications of increasing uterine weight at the time of hysterectomy for endometrial cancer.

Objectives: Research on endometrial cancer (EC) has demonstrated an association between increasing tumor size and poor outcomes, including increase in nodal disease and advanced stage at diagnosis. However, the implications of overall uterine weight (UW) at the time of hysterectomy for EC are unknown. The aim of this study is to investigate if increasing UW is associated with poor prognosis, specifically regarding lymph node metastasis (LNM), lymphovascular space invasion (LVSI), and stage. Materials and Methods: This is a retrospective cohort study of patients undergoing robotic-assisted surgical management of EC at two institutions. Patients with a preoperative diagnosis of complex atypical hyperplasia (CAH) or EC were included. All patients underwent surgical staging including hysterectomy, bilateral salpingo-oophorectomy, pelvic lymphadenectomy, and when feasible, para-aortic lymphadenectomy. Patients were categorized based on UW on final pathology report, into one of six groups: < 50 grams, 51-100 grams, 101-150 grams, 151-200 grams, 201-250 grams, and > 250 grams. The rate of lymph node involvement, LVSI, and stage were then analyzed for each group. Chi-Square and t-test were used for statistical analysis. Results: From 2013-2017, 161 patients were identified. Twenty-seven patients were excluded due to final pathology diagnosis other than EC. Of the remaining 134 patients, 103 had LVSI, 96 had LNM and 116 had stage reported. There were 120 (89.6%) endometrioid, four (2.9%) papillary serous, three (2.2%) clear cell, three (2.2%) carcinosarcoma, three (2.2%) undifferentiated, and one (0.7%) endometrial stromal sarcoma histologies. Among the entire cohort, the incidence of LNM was 19.8% and LVSI was 12.6%. Increasing UW was associated with increase in LVSI (p = 0.003), LN metastasis (p = 0.000), and stage (p = 0.010). On further analysis, the cohort was examined as two separate groups, UW < 200 vs. > 200 grams. UW > 200 grams is associated with significant increase in LVSI (p = 0.045) and LNM (p = 0.0005). There were no LNM in patients with UW < 100 grams. Conclusions: Increasing UW at the time of hysterectomy for EC is associated with increase in LVSI, LN metastasis, and stage. [ABSTRACT FROM AUTHOR]