SRS307 - A perfused human pancreatic cancer model for evaluating loco-regional therapies: a feasibility study supporting the 3Rs

Abstract Background Pancreatic ductal adenocarcinoma (PDAC) remains one of the most treatment-resistant malignancies, with less than 1% of novel therapeutic agents reaching clinical use. Traditional in vivo and in vitro models fail to fully recapitulate the tumour microenvironment. We describe an ex vivo perfusion model using resected human PDAC tissue to evaluate irreversible electroporation (IRE) of pancreatic cancer. Methods Fresh PDAC specimens from patients undergoing resection at a tertiary centre were cannulated and perfused within 30 min of surgery using a custom-built sub-normothermic perfusion circuit. The perfusate used expired human red blood cells. IRE was applied during perfusion. Tru-Cut biopsies were taken at baseline (before perfusion or ablation) and every 5 min for 30 min. Tissue viability was assessed by haematoxylin and eosin staining and cleaved caspase-3 immunohistochemistry. The Apoptotic Index (AI) was determined using ImageJ analysis. Results Three human PDAC specimens were perfused and ablated. A total of 36 biopsies were taken. Two samples were treatment-naïve, and one had received neoadjuvant chemotherapy. Post-IRE biopsies showed increased cleaved caspase-3 expression in a voltage-dependent manner. At 30 min post-ablation, mean Apoptotic Index in ablated samples reached 3.64% (1400 V/cm), 4.87% (1800 V/cm), and 15.62% (2000 V/cm), compared to 1.94, 1.74, and 2.74% respectively in non-ablated counterparts, indicating a voltage-dependent and spatially specific increase in apoptosis. Conclusions This ex vivo perfusion model enables histological assessment of loco-regional therapies such as IRE in human PDAC tissue. It supports the 3Rs by reducing reliance on animal models, which poorly mimic pancreatic cancer.