Predictors for the Recurrence of Clinically Uterine-Confined Endometrial Cancer and the Role of Cytokeratin Immunohistochemistry Stain in the Era of Sentinel Lymph Node Mapping

SIMPLE SUMMARY: Sentinel lymph node (SLN) mapping in women with endometrial cancer is gradually gaining popularity worldwide. The objectives of this retrospective study were to elucidate the predictors for cancer recurrence in the era of SLN mapping, and to compare the clinical outcomes between SLN mapping and traditional lymphadenectomy, as well as to investigate the role of cytokeratin immunohistochemistry stain in detecting lymph node metastases. Para-aortic lymph node metastasis was found to be the sole predictor for cancer recurrence. Cytokeratin immunohistochemistry stain detects more lymph node metastases. In addition, both SLN mapping and traditional lymphadenectomy have similar probabilities of cancer recurrence. ABSTRACT: Background: The primary objective of this study was to elucidate the predictors for cancer recurrence in women with clinically uterine-confined endometrial cancer in the era of sentinel lymph node (SLN) mapping. Methods: All consecutive women with clinically determined uterine-confined endometrial cancer who had lymph node assessment by either SLN mapping or traditional pelvic lymphadenectomy were reviewed. Results: Women in the SLN mapping group had lower total dissected pelvic nodes, lower incidence of para-aortic lymph node dissection, less intraoperative blood loss and lower complication rates, but a longer operation time compared to the traditional lymphadenectomy group. Para-aortic lymph node metastasis (hazard ratio = 7.60, p = 0.03) was the sole independent predictor for recurrence-free survival. In addition, the utilization of cytokeratin immunohistochemistry stain detected more lymph node metastases (adjusted odds ratio = 3.04, p = 0.03). Recurrence-free survival did not differ between SLN mapping and traditional lymphadenectomy groups (p = 0.24). Conclusions: Para-aortic lymph node metastasis is an important predictor of cancer recurrence. Women with negative hematoxylin and eosin stain should undergo cytokeratin immunohistochemistry stain to increase the detection rate of positive lymph node metastasis. Besides, the probabilities of recurrence seem to be similar between SLN mapping and traditional lymphadenectomy groups in women with clinically uterine-confined endometrial cancer.