Which Factors Are Important for Successful Sentinel Node Navigation Surgery in Gastric Cancer Patients? Analysis from the SENORITA Prospective Multicenter Feasibility Quality Control Trial

Background. We investigated the results of quality control study prior to phase III trial of sentinel lymph node navigation surgery (SNNS). Methods. Data were reviewed from 108 patients enrolled in the feasibility study of laparoscopic sentinel basin dissection (SBD) in gastric cancer. Seven steps contain tracer injection at submucosa (step 1) and at four sites (step 2) by intraoperative esophagogastroduodenoscopy (EGD), leakage of tracer (step 3), injection within 3 minutes (step 4), identification of at least one sentinel basin (SB) (step 5), evaluation of sentinel basin nodes (SBNs) by frozen biopsy (step 6), and identification of at least five SBNs at back table and frozen sections (step 7). Results. Failure in step 7 (n=23) was the most common followed by step 3 (n=15) and step 6 (n=13). We did not find any differences of clinicopathological factors between success and failure group in steps 1~6. In step 7, body mass index (BMI) was only the significant factor. The success rate was 97.1% in patients with BMI 2 and 80.3% in those with BMI ≥ 23 kg/m2 (P=0.028). Conclusions. Lower BMI group showed higher success rate in step 7. Surgeons doing SNNS should be cautious when evaluating sufficient number of SBN in obese patients.