An Extraordinary Location of Sentinel Lymph Nodes in a Patient with Endometrial Cancer.

Objective: To show dissection of sentinel lymph nodes.

Design: A step-by-step demonstration of the technique with narration.

Setting: Endometrial cancer (EC) is the most common gynecologic malignancy worldwide. Sentinel lymph node biopsy with indocyanine green (ICG) has become more widely used and has been featured in recently published guidelines for EC [1]. Minimally invasive approaches with the sentinel lymph node concept (conventional laparoscopy, laparoscopic-assisted vaginal surgeries or robotic) to EC staging have resulted in lower rates of peri- and postoperative complications than conventional staging procedures [2].

Interventions: No video article has been published in the literature about high pelvic, para-aortic sentinel lymph node dissection. An informed consent form was obtained from the patient. An institutional review board approval was not required. A 45-year-old female with gravidity 0, parity 0, and body mass index of 23.4 kg/m presented with complaints of abnormal uterine bleeding (spotting). Increased endometrial thickness was detected on transvaginal ultrasound (10 mm) in the postmenstrual period. Endometrioid-type endometrial adenocancer with focal squamous differentiation International Federation of Gynecology and Obstetrics grade I was detected on endometrial biopsy. The patient had hepatitis B virus positivity and no other chronic disease. A laparotomic myomectomy had been performed in 2016. Laparoscopic high pelvic, low para-aortic sentinel lymph node dissection with ICG and hysterectomy (without uterine manipulator) + bilateral salpingo-oophorectomy were performed (Supplemental Video 1). The operation time for the procedure was 110 minutes and the estimated blood loss was <20 mL. No major complications occurred during or after the surgery. The patient stayed in the hospital for 1 day. The final pathology result showed an International Federation of Gynecology and Obstetrics grade I, endometrioid-type endometrial adenocancer with focal squamous differentiation, as a 1.5 × 1 cm tumorous mass invading less than one-half of the myometrium. Neither lymphovascular invasion nor sentinel lymph node metastasis was detected. A multicenter, prospective study showed that sentinel lymph node dissection with ICG in clinical stage 1 EC is feasible and has a high degree of diagnostic accuracy in detecting EC metastases. In that study, isolated para-aortic sentinel lymph node was detected in 3 of 340 patients (<1%) [2]. Another study reported the detection rate of isolated para-aortic sentinel lymph node to be 1.1% in patients with intermediate- and high-risk EC [3].

Conclusion: There are in some cases 2 distinct channels emanating from one side, and it is important to follow each and to acknowledge there may be more than one sentinel, one of which is lower in a typical location and one higher as in this case. This video article is the first video demonstration of bilateral isolated high pelvic, para-aortic sentinel lymph node dissection in EC.