Portomesenteric venous contact ≤180° and overall survival in resectable head and body pancreatic adenocarcinoma treated with upfront surgery.

INTRODUCTION: Upfront surgery is the standard of care for resectable pancreatic cancer, defined as the absence of or ≤180° tumour contact with the portal/superior mesenteric vein. We hypothesized that portomesenteric venous tumour contact is prognostically unfavourable and aimed to assess whether it is associated with poorer survival compared with no venous contact in resectable head and body pancreatic cancer. METHODS: This single-centre retrospective study included patients undergoing upfront surgery for resectable head and body pancreatic cancer in 2010-2020 at Umeå University Hospital, Sweden. No venous contact was compared with portomesenteric venous contact of ≤180° based on preoperative imaging. Overall survival on an intention-to-treat basis was compared with Kaplan-Meier curves, a log-rank test and Cox proportional hazards models. RESULTS: The final study cohort included 39 patients with portomesenteric venous tumour contact and 144 patients without venous tumour contact. Patients with venous tumour contact had a median overall survival of 15.3 months compared to 23.0 months (log rank P = 0.059). Portomesenteric venous tumour contact was an independent negative prognostic factor for survival in the multivariable Cox model (HR 1.68; 95% CI 1.11-2.55, P = 0.014) and was associated with higher rates of microscopically non-radical resections (R1) (50% vs 26.1%, P = 0.012) and pathological lymph node metastasis (76.7% vs 56.8%, P = 0.012). There was no difference in adjuvant chemotherapy receipt or postoperative complications between the groups. CONCLUSIONS: Portomesenteric venous tumour contact is associated with poorer overall survival and higher rates of R1 resections and lymph node metastasis in patients with resectable head and body pancreatic cancer treated with upfront surgery.

3D culturing and differentiation of SH-SY5Y neuroblastoma cells on bacterial nanocellulose scaffolds.

A new in vitro model, mimicking the complexity of nerve tissue, was developed based on a bacterial nanocellulose (BNC) scaffold that supports 3D culturing of neuronal cells. BNC is extracellularly excreted by Gluconacetobacter xylinus (G. xylinus) in the shape of long non-aggregated nanofibrils. The cellulose network created by G. xylinus has good mechanical properties, 99% water content, and the ability to be shaped into 3D structures by culturing in different molds. Surface modification with trimethyl ammonium beta-hydroxypropyl (TMAHP) to induce a positive surface charge, followed by collagen I coating, has been used to improve cell adhesion, growth, and differentiation on the scaffold. In the present study, we used SH-SY5Y neuroblastoma cells as a neuronal model. These cells attached and proliferated well on the BNC scaffold, as demonstrated by scanning electron microscopy (SEM) and the 3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium) (MTS) assay. Following neuronal differentiation, we demonstrated functional action potentials (APs) by electrophysiological recordings, indicating the presence of mature neurons on the scaffolds. In conclusion, we have demonstrated for the first time that neurons can attach, proliferate, and differentiate on BNC. This 3D model based on BNC scaffolds could possibly be used for developing in vitro disease models, when combined with human induced pluripotent stem (iPS) cells (derived from diseased patients) for detailed investigations of neurodegenerative disease mechanisms and in the search for new therapeutics.