Hysteroscopic compared to cervical injection for sentinel node detection in endometrial cancer: a multicenter prospective randomized controlled trial

Introduction/Background* In the last decade, sentinel lymph node mapping (SLNM) has gained a central role in endometrial cancer (EC) surgical staging. However, different technical steps of SLNM still remain object of discussione. Terofere, a randomized control trial (RCT) was conducted to compare cervical and hysteroscopic indocyanine green (ICG) injection for SLNM of newly diagnosed EC undergoing surgical staging. The prima-ry endpoint of the study was to compare these two techniques in term of para-aortic detection rate. Methodology This RCT included women with apparent stage I or II histologically confirmed endometrial cancer undergoing surgery were included in the study. Two groups were distinguished according to two different techniques of indocyanine green (ICG) sentinel lymph node mapping (SLNM): cervical versus hysteroscopic injection. This randomized trial was not blinded for both the patients and the surgeons. Result(s)* Since March 2017 until April 2019, 165 patients were randomized: 85 (51.5%) in the cervical group and 80 (48.5%) in the hysteroscopic group. After randomization, 14 (8.5%) patients were excluded from the study. Finally, 151 patients were included in the analysis: 82 (54.3%) in the cervical group and 69 (45.7%) in the hysteroscopic group. Hysteroscopy injection demonstrated a 10% higher accuracy to detect SNLs in the paraaortic area compared to cervical injection, although this difference did not reach statistical significance. The hysteroscopic technique was better in detecting isolated SLN para-aortic (5.8% vs 0%). Cervical injection was correlated with higher SLN detection rates at pelvic level compared to hysteroscopic injection. Pelvic and overall detection was superior in the cervical group. Conclusion* The current study suggests the use of cervical injection rather than hysteroscopic injection due to its better identification of sentinel nodes (particularly in the pelvic area). Although, detection of SLN in the para-aortic area was slightly superior in patients undergoing a hysteroscopic injection, no significant difference with cervical injection was detected.