A preoperative risk-scoring system to predict lymph node metastasis in endometrial cancer and stratify patients for lymphadenectomy

• Our preoperative scoring system can accurately predict rate of lymph node metastasis in endometrial cancer.
• Lymphadenectomy can be safely omitted for endometrial cancer patients with no risk of lymph node metastasis.
• Our scoring system can determine extent of lymphadenectomy for patients with risk of lymph node metastasis.

ObjectiveThis study aimed to validate the preoperative scoring system adopted in the Kanagawa Cancer Center (KCC) to stratify endometrial cancer patients for lymphadenectomy according to the risk of developing lymph node metastasis (LNM).MethodsThe records of 432 and 221 uterine cancer patients treated in the KCC and Yokohama City University (YCU), respectively, were retrospectively analyzed. The KCC classified patients for LNM risk based on tumor volume, myometrial invasion, histological grade, and serum CA125 levels, while YCU used only myometrial invasion. Lymphadenectomy was omitted for 156 patients with 0 LNM risk, while pelvic lymphadenectomy (PLX) or PLX with para-aortic lymphadenectomy (PLAX) were performed for those with low and high LNM risk, respectively. The predicted and actual LNM rates were compared between the KCC and YCU patients, and cancer recurrence and overall survival were analyzed.ResultsThere was no difference in survival between patients with LNM score 0 who were or were not treated with lymphadenectomy. None (0%) developed LNM and only 1 (0.6%) had recurrence. Patients who underwent PLX but not PLAX (low LNM score) had a low tumor recurrence rate in the para-aortic nodes (1.3%). The KCC scoring system was significantly more accurate than the YCU system in predicting LNM in the high-risk group (P < 0.05) and demonstrated that PLAX was unnecessary in almost 50% of the YCU cases.ConclusionThe KCC preoperative scoring system is useful to predict LNM risk, and thereby prevent unnecessary lymphadenectomy or to determine its extent in endometrial cancer patients.