The Utility of Sentinel Lymph Node Mapping in High-Grade Endometrial Cancer

Abstract

ObjectiveThe aim of this study was to report the utility and false-negative rates of sentinel lymph node (SLN) mapping during surgical staging of women with high-grade, apparent uterine-confined endometrial cancer.MethodsThis was a single-institution study performed at a high-volume academic center. From December 2012 to December 2015, women with high-grade endometrial cancer (grade 3 endometrioid, serous, clear cell, and carcinosarcoma) underwent SLN mapping via cervical injection followed by robot-assisted total laparoscopic hysterectomy and completion lymphadenectomy. Ultrastaging of SLNs was performed in patients with tumors with any degree of myoinvasion. Patient demographics, SLN test characteristics, treatment, and recurrence outcomes were prospectively evaluated for analysis.ResultsFifty-two patients with high-grade histologic findings underwent SLN mapping followed by completion lymphadenectomy. The median patient age was 64 years, and median body mass index was 31.8 kg/m2. Most patients had either serous (46%) or grade 3 endometrioid histology (27%) on preoperative biopsy. Nine patients had nodal metastases, 7 of whom had metastases identified in SLNs. No low-volume nodal metastases were identified on ultrastaging. Two patients had false-negative SLN mapping (22%). After a median follow-up of 15.6 months, 14 recurrences (27%) were diagnosed; all were distant or multisite relapses. Sentinel lymph node mapping did not impact the choice of adjuvant therapy or recurrence risk in node-positive patients.ConclusionsSentinel lymph node detection of metastases in patients with high-grade endometrial cancer is high, but false-negative results were encountered. More research is needed to determine whether SLN mapping can safely replace systemic lymphadenectomy in women with high-risk histologic findings.

Paraaortic sentinel lymph node detection in intermediate and high-risk endometrial cancer by transvaginal ultrasound-guided myometrial injection of radiotracer (TUMIR)

“…The intraoperative SLN detection rate in the present series was almost 80%, being slightly lower than the rate observed in previous studies performed with cervical tracer injection in intermediate or high-risk EC, in which the SLN detection rate ranged from 83% to 100% [ 3 4 6 8 18 19 20 21 22 23 24 25 ]. Two studies evaluating the SLN procedure with subserosal injection of blue dye in intermediate and/or high-risk EC patients showed detection rates of 73% and 89% [ 26 27 ].…”

Robotic sentinel lymph node (SLN) mapping in endometrial cancer: SLN symmetry and implications of mapping failure

“…As SLN mapping continues to become more widely used in the surgical staging process of early endometrial cancer, it is increasingly important to understand mapping patterns and limitations. While SLN mapping has a high sensitivity and negative predictive value in identifying nodal metastasis, there remains an important role for completion lymphadenectomy when SLN mapping fails 3 8 9…”

“…However, limited evidence exists to explain why SLN mapping fails in endometrial cancer. Some have proposed factors such as cervical or uterine lengths, large tumors, deep myometrial invasion,2 obesity, fibroids, or bulky metastasis3 may contribute to mapping failure. It has been demonstrated in breast cancer that patients with extensive nodal involvement are more likely to fail SLN mapping,4 possibly because of tumor cells obstructing lymphatics.…”

Frozen section accurately allows pathological characterization of endometrial cancer in patients with a preoperative ambiguous or inconclusive diagnoses: our experience

“…IOE is also important for the evaluation of lymh-nodes status; in fact the use of sentinel node, as intraoperative surgical staging tool, has been implemented in the last years in order to avoid staging lymphadenectomy in low-risk EC patients according to ‘Mayo criteria’ grade 1 or 2 disease, < 50% myometrial invasion, and tumor diameter < 2 cm) [6]. On the other hand, in high risk patients (endometrioid grade 3, clear cell, serous, and carcinosarcoma) the same procedure has no impact in the choice of adjuvant therapy and more studies are still needed to determine if SLN mapping could replace total lymphadenectomy [7].…”