Omental patch versus gastric resection for perforated gastric ulcer: Systematic review and meta-analysis for an unresolved debate.

BACKGROUND: Perforated gastric ulcers are surgical emergencies with paucity of data on the preferred treatment modality of resection versus omental patch. We aim to compare outcomes with ulcer repair and gastric resection surgeries in perforated gastric ulcers after systematic review of literature. METHODS: A systematic literature search was performed for publications in PubMed Medline, Embase, and Cochrane Central Register of Controlled Trials. We included all studies which compared ulcer repair vesus gastric resection surgeries for perforated gastric ulcers. We excluded studies which did not separate outcomes gastric and duodenal ulcer perforations. RESULTS: The search included nine single-institution retrospective reviews comparing ulcer repair (449 patients) versus gastric resection surgeries (212 patients). Meta-analysis was restricted to perforated gastric ulcers and excluded perforated duodenal ulcers. The majority of these studies did not control for baseline characteristics, and surgical strategies were often chosen in a non-randomized manner. All of the studies included were at high risk of bias. The overall odds ratio of mortality in ulcer repair surgery compared to gastric resection surgery was 1.79, with 95% CI 0.72 to 4.43 and p-value 0.209. CONCLUSION: In this meta-analysis, there was no difference in mortality between the two surgical groups. The overall equivalence of clinical outcomes suggests that gastric resection is a potentially viable alternative to ulcer repair surgery and should not be considered a secondary strategy. We would recommend a multicenter randomized control trial to evaluate the surgical approach that yields superior outcomes. LEVEL OF EVIDENCE: Systematic review and meta-analysis, level III.

3D microfluidic ex vivo culture of organotypic tumor spheroids to model immune checkpoint blockade.

Microfluidic culture has the potential to revolutionize cancer diagnosis and therapy. Indeed, several microdevices are being developed specifically for clinical use to test novel cancer therapeutics. To be effective, these platforms need to replicate the continuous interactions that exist between tumor cells and non-tumor cell elements of the tumor microenvironment through direct cell-cell or cell-matrix contact or by the secretion of signaling factors such as cytokines, chemokines and growth factors. Given the challenges of personalized or precision cancer therapy, especially with the advent of novel immunotherapies, a critical need exists for more sophisticated ex vivo diagnostic systems that recapitulate patient-specific tumor biology with the potential to predict response to immune-based therapies in real-time. Here, we present details of a method to screen for the response of patient tumors to immune checkpoint blockade therapy, first reported in Jenkins et al. Cancer Discovery, 2018, 8, 196-215, with updated evaluation of murine- and patient-derived organotypic tumor spheroids (MDOTS/PDOTS), including evaluation of the requirement for 3D microfluidic culture in MDOTS, demonstration of immune-checkpoint sensitivity of PDOTS, and expanded evaluation of tumor-immune interactions using RNA-sequencing to infer changes in the tumor-immune microenvironment. We also examine some potential improvements to current systems and discuss the challenges in translating such diagnostic assays to the clinic.