Comparison of lymph node evaluation and yield among patients undergoing open and minimally invasive surgery for gallbladder adenocarcinoma.

INTRODUCTION: Assessment of regional lymph nodes (LN) is essential for determining prognosis among patients with gallbladder cancer (GBC). The impact of surgical technique on LN yield has not been well explored. We investigated the impact of minimally invasive surgery (MIS; robotic or laparoscopic) on the evaluation and retrieval of regional LN for patients with GBC. METHODS: We queried the National Cancer Database (NCDB) to identify patients with GBC who underwent curative-intent surgery between 2010 and 2015. Patients with metastatic disease or those with missing data on surgical resection or LN evaluation were excluded. RESULTS: We identified 2014 patients who underwent an open (n = 1141, 56.6%) or MIS approach (n = 873, 43.4%) for GBC and met the inclusion criteria. Patients who underwent MIS were older (open: 68 years, IQR: 60, 75 vs. MIS: 70 years, IQR (61, 77); P = 0.02), and were more commonly treated at a comprehensive community cancer program (P < 0.001). Approximately 3 out of 4 patients (n = 1468, 72.9%) underwent an evaluation of regional LN, with nearly half of these patients (n = 607, 41.7%) having LN metastasis. Among patients who underwent a regional lymphadenectomy, average lymph node yield was 3 (IQR: 1, 6) and was similar between the two groups (P = 0.04). After controlling for all factors, operative approach was not associated with likelihood of receiving a lymphadenectomy during curative-intent resection (OR 0.81, 95% CI 0.63-1.04; P = 0.11). CONCLUSION: In conclusion, patients undergoing curative-intent resection for GBC had similar rates of lymph node evaluation and yield regardless of operative approach. Over one-quarter of patients did not undergo a lymphadenectomy at the time of surgery. Further studies are needed to identify barriers to lymph node evaluation and yield among patients undergoing surgery for gallbladder cancer. Presented at the 2019 2nd World Congress of the International Laparoscopic Liver Society, Tokyo, Japan.