No abstract

e16656 Background: Neoadjuvant immunotherapy with anti-programmed cell death protein-1 (PD-1) or anti-programmed cell death ligand-1 (PD-L1) and tyrosine kinase inhibitor (TKI) therapy is currently being used to treat certain solid tumours prior to surgery. Neoadjuvant therapy may cause delays to resection potentially losing a window of opportunity. We explored the pooled proportion of patients with solid tumours receiving neoadjuvant therapy who completed planned surgical resection. Methods: Medline, CENTRAL and Embase databases were searched for single arm or randomized controlled trials studying neoadjuvant PD-1/PD-L1 immunotherapy or TKI therapy. Random-effects model was used to estimate the pooled proportion of patients undergoing planned resection, and weights were estimated using inverse variance method. Statistical heterogeneity was calculated using the I2 and chi-squared test. Results: From 368 relevant articles, eleven studies with a total of 382 patients receiving neoadjuvant PD-1 immunotherapy (n = 234) or neoadjuvant TKI therapy (n = 148) were analyzed. The types of tumours included hepatocellular carcinoma (1 study), renal cell carcinoma (8 studies), bladder carcinoma (1 study) or non-small cell lung cancer (1 study). The pooled proportion of patients who completed planned surgery after neoadjuvant therapy was 95% (95% CI 0.92 to 0.99). The overall partial response rate prior to surgery was 12% (95% CI 0.07 to 0.16) in the PD-1 therapy group and 46% (95% CI -0.12 to 1.03) in the TKI group. The pooled serious adverse events rate was 17% (95% CI 0.02 to 0.32) in the PD-1 therapy group and 29% (95% CI -0.10 to 0.68) in the TKI group. For all patients receiving neoadjuvant therapy, the pooled median overall survival was 23.41 months (95% CI 16.21 to 30.62) and median progression free survival was 7.46 months (95% CI 4.41 to 10.51). Conclusions: Neoadjuvant PD-1 or TKI therapy prior to surgery for solid tumours is safe, does not delay surgical resection and can result in a partial radiological response prior to surgery.

University Background: Approximately 10-40% of patients undergoing pancreatectomy develop postoperative pancreatic fistula (POPF). Currently, conservative management focusing on nutritional optimization is widely applied in the setting of POPF. However, there is no consensus on the most effective route for administration of nutrients in this setting. We aimed to compare the efficacy of parenteral nutrition (control) versus enteral nutrition (intervention) in the rate of POPF closure. Methods: Medline, EMBASE, CENTRAL, and Web of Science databases were searched for randomized controlled trials comparing enteral to parenteral nutrition in the conservative management of POPF and reported time to POPF closure. Quality was assessed using the Cochrane Risk of Bias Tool and quality of pooled evidence was assessed using GRADE. Results: From 2,682 relevant citations, three studies including a total of 167 pateints were analyzed (85 patients in the enteral group and 82 patients in the parenteral group. The mean time to POPF closure was 3.46 days shorter in the enteral group (experimental) than the parenteral group (control), which failed to reach statistical significance (95% CI-1.39 to 8.31, P = 0.30, I2). The complication rates in both groups were low and there were no significant differences in complication rate (OR 1.69, 95% CI 0.52 to 5,47, P = 0.38) or length of stay (95% CI-9.21 to 10.74, P = 0.88). Conclusion: The rate of POPF closure is equivalent in patients receiving enteral feeds compared to those receiving parenteral feeds. The choice between enteral and parenteral feeds in the conservative management of POPF should be determined by individual patient factors.

Background: Postoperative pancreatic fistula (POPF) remains a significant source of morbidity following pancreatic surgery. The most effective feeding route for the conservative management of POPF is currently unknown. We aimed to compare the efficacy of enteral to parenteral nutrition in the rate of POPF closure. Methods: Medline, EMBASE, CENTRAL, and Web of Science were searched for randomized controlled trials (RCTs) comparing enteral to parenteral nutrition in the conservative management of POPF. Risk of bias was assessed using the Cochrane Risk of Bias Tool. Quality of the evidence was assessed using GRADE. Random-effects meta-analysis was used to estimate time to POPF closure. Results: From 2,682 citations, three RCTs (n=167) were included (enteral group, n=85; parenteral group, n=82). Mean time to POPF closure was 3.64 days shorter in the enteral than the parenteral group, which was not statistically significant (95% CI-3.22 to 10.49, P = 0.30). There were no significant differences in postoperative complication rate (OR 1.69, 95% CI 0.52 to 5.47, P = 0.38) or length of hospital stay between groups (mean difference: 0.76, 95% CI-9.21 to 10.74, P = 0.88). According to GRADE, the overall certainty of the evidence for the main outcome was very low. Conclusions: There was no data to suggest that enteral nutrition is more effective than parenteral nutrition at enhancing the rate of POPF closure. However, the quality of evidence that currently exists is very low. Therefore, the decision between enteral and parenteral nutrition in this setting should still be based on physician preference and patient specific factors.

511 Background: Neoadjuvant immunotherapy with anti-programmed cell death protein-1 (PD-1) or anti-programmed cell death ligand-1 (PD-L1) and tyrosine kinase inhibitor (TKI) therapy is currently being used to treat certain solid tumours prior to surgery. Neoadjuvant therapy may cause delays to resection potentially losing a window of opportunity. We explored the pooled proportion of patients with solid tumours receiving neoadjuvant therapy who completed planned surgical resection. Methods: Medline, CENTRAL and Embase databases were searched for single arm or randomized controlled trials studying neoadjuvant PD-1/PD-L1 immunotherapy or TKI therapy. Random-effects model was used to estimate the pooled proportion of patients undergoing planned resection, and weights were estimated using inverse variance method. Statistical heterogeneity was calculated using the I2 and chi-squared test. Results: From 368 relevant articles, eleven studies with a total of 382 patients receiving neoadjuvant PD-1 immunotherapy (n = 234) or neoadjuvant TKI therapy (n = 148) were analyzed. The types of tumours included hepatocellular carcinoma (1 study), renal cell carcinoma (8 studies), bladder carcinoma (1 study) or non-small cell lung cancer (1 study). The pooled proportion of patients who completed planned surgery after neoadjuvant therapy was 95% (95% CI 0.92 to 0.99). The overall partial response rate prior to surgery was 12% (95% CI 0.07 to 0.16) in the PD-1 therapy group and 46% (95% CI -0.12 to 1.03) in the TKI group. The pooled serious adverse events rate was 17% (95% CI 0.02 to 0.32) in the PD-1 therapy group and 29% (95% CI -0.10 to 0.68) in the TKI group. For all patients receiving neoadjuvant therapy, the pooled median overall survival was 23.41 months (95% CI 16.21 to 30.62) and median progression free survival was 7.46 months (95% CI 4.41 to 10.51). Conclusions: Neoadjuvant PD-1 or TKI therapy prior to surgery for solid tumours is safe, does not delay surgical resection and can result in a partial radiological response prior to surgery.