Hepato-pancreato-biliary (HPB) cancer is a serious category of cancer including tumors originating in the liver, pancreas, gallbladder and biliary ducts. It is limited by two-dimensional (2D) cell culture models for studying its complicated tumor microenvironment including diverse contents and dynamic nature. Recently developed three-dimensional (3D) bioprinting is a state-of-the-art technology for fabrication of biological constructs through layer-by-layer deposition of bioinks in a spatially defined manner, which is computer-aided and designed to generate viable 3D constructs. 3D bioprinting has the potential to more closely recapitulate the tumor microenvironment, dynamic and complex cell-cell and cell-matrix interactions compared to the current methods, which benefits from its precise definition of positioning of various cell types and perfusing network in a high-throughput manner. In this review, we introduce and compare multiple types of 3D bioprinting methodologies for HPB cancer and other digestive tumors. We discuss the progress and application of 3D bioprinting in HPB and gastrointestinal cancers, focusing on tumor model manufacturing. We also highlight the current challenges regarding clinical translation of 3D bioprinting and bioinks in the field of digestive tumor research. Finally, we suggest valuable perspectives for this advanced technology, including combination of 3D bioprinting with microfluidics and application of 3D bioprinting in the field of tumor immunology.

BackgroundThe prognostic value of the tumor burden score (TBS) in patients with combined hepatocellular-cholangiocarcinoma (cHCC-CCA) remains unknown. This study aimed to investigate the impact of TBS on long-term outcomes after surgery.MethodsPatients who underwent radical-intent resection between June 2013 and December 2019 were retrospectively reviewed. Kaplan–Meier curves were used to analyze patient survival, and disease-free survival (DFS) and overall survival (OS) were examined in relation to TBS.ResultsA total of 178 patients were included in this study, with 119 in the training cohort and 59 in the validation cohort. Kaplan–Meier curves showed that TBS was a strong prognostic indicator in patients with cHCC-CCA. Elevated TBS was associated with poorer DFS and OS (both P-value < 0.001) and was identified as an independent prognostic indicator. In addition, the prognostic value of TBS outperformed tumor size and number alone, microvascular invasion, and lymph node invasion. The prognostic significance of TBS was confirmed by the internal validation cohort.ConclusionsThe present study suggested the significance of tumor morphology in assessing the prognosis of patients with cHCC-CCA who undergoing curative resection. The TBS is a promising prognostic index in patients with cHCC-CCA. Elevated TBS was related to a lower long-term survival rate and was identified as an independent risk factor for poor DFS and OS. Further research is needed to verify our results.