The role of cytoreductive surgery for recurrent endometrial cancer

Abstract

Objectives: To determine the rate and performance of sentinel lymph node (SLN) mapping among women with high-risk endometrial cancers. Methods: Patients diagnosed between 2012 and 2014 with uterine cancer of grade 3 endometrioid, clear cell, serous, or carcinosarcoma histology who underwent SLN mapping before full lymph node dissection were included. Patients underwent either methylene blue or indocyanine green injection for laparoscopic (n = 15) or roboticassisted laparoscopic staging (n = 12). Outcomes examined included rates of SLN mapping using each surgical approach, SLN and non-SLN positive rates, false-negative SLN rate, and the negative predictive value of SLN. Ultrastaging of SLN was not routinely performed during the study period. Fisher's exact test was used to compare mapping and node positivity rates. Results: A total of 10/27 (37%) patients with high-risk uterine cancer had at least one positive lymph node identified. Twelve patients (44%) mapped bilaterally, 10 (37%) mapped unilaterally, and 5 (18%) did not map. Thirty-four of 54 sides (63%) mapped successfully. Successful SLN mapping rates by side were: 19/30 sides (63%) for the laparoscopic and 15/24 sides (66%) for the robotic approach (P=0.53). Among 20 sides that failed to map, 4 (26%) had findings of grossly enlarged nodes, 7 (35%) had reportable adhesions, 6 (30%) had fibroids, and 4 (20%) were morbidly obese, making node visualization difficult. Nine of 75 (12%) sentinel nodes and 8/513 (2%) nonsentinel nodes were positive (P = 0.0009). Eight of nine (89%) positive SLNs were the only positive lymph nodes identified on that side. The false-negative SLN rate (negative SLN but other malignant lymph nodes identified on the same side) was 1/20 (5%); the negative predictive value of SLN was 95%. Conclusions: In this series of women with high-risk uterine cancer, SLNs had a significantly higher rate of metastasis than nonsentinel lymph nodes. However, successful mapping rates may be slightly lower than historical controls among high-risk histology cancers. The 95% negative predictive value of SLN is consistent with larger subsets of lower risk endometrial cancers.