Impact of Neoadjuvant Therapy on Minimally Invasive Surgical Outcomes in Advanced Gastric Cancer: An International Propensity Score-Matched Study

Background No international consensus on the treatment of advanced gastric cancer (AGC) exists. In the absence of well-designed, comparative studies between neoadjuvant versus adjuvant strategies, concerns about increased risk of postoperative complications remain barriers to neoadjuvant chemotherapy (NAC) for AGC. We evaluated surgical outcomes of AGC patients who received minimally invasive radical gastrectomy with D2 lymphadenectomy after NAC. Methods We collected data from two high-volume gastric cancer programs in the United States and China between January 2015 and December 2019 with the last follow-up in February 2020. AGC patients undergoing minimally invasive radical surgery were included. After propensity score-matching, surgical outcomes were analyzed. Risk-factor of complications was analyzed in the whole cohort. Results After 1:1 propensity score-matching, 97 patients were included in each cohort. NAC + surgery cohort was younger (58.2 +/- 10.3 vs. 61.3 +/- 9.6,P = 0.036) with lower preoperative WBC count (5.7 +/- 2.8 vs. 6.9 +/- 2.1 x 10(9)/ml) than the surgery upfront cohort. NAC was not a risk-factor for postoperative complications (odds ratio [OR], 0.859; 95% confidence interval [CI], 0.46-1.60;P = 0.633). Overall risk-factors of postoperative complications included age >= 60 years (OR, 21.338; 95% CI, 5.00-91.05;P < 0.001), tumor size >= 5 cm (OR, 1.24; 95% CI, 1.08-1.83;P < 0.001), operation time >= 240 min (OR, 5.53; 95% CI, 1.26-24.26;P = 0.012), and ASA classification >= II (OR, 13.14; 95% CI, 4.12-24.73;P < 0.001). Conclusions NAC before minimally invasive radical gastrectomy with D2 lymphadenectomy does not increase postoperative complications, and these findings support broader application of NAC and MIS for AGC. Additional studies are required to determine the effect of NAC on long-term survival.