Endovascular light-activated ablation to downstage locally advanced pancreatic cancers touching major blood vessels to assess feasibility for surgical excision

Many pancreatic cancers present with the tumour apparently adherent to major blood vessels, hindering surgery. Anecdotal reports of cancers like this treated with interstitial, image guided, percutaneous photodynamic therapy show that cancers may shrink, revealing a resection plane between tumour and blood vessel, making surgical resection feasible with an improved prognosis. In a new approach using endovascular light-activated ablation, 7 normal pigs were photosensitised with Verteporfin and light delivered into a major vessel to induce necrosis in the adjacent pancreas and assess effects on the vessel wall. 48h after light-activation, necrosis up to 15mm deep was achieved in normal pancreas adjacent to the blood vessel. The vessel showed endothelial sloughing and inflammatory changes that previous studies had shown heal safely without threat to its mechanical integrity. Endovascular light-activated ablation may have a role in making more locally advanced pancreatic cancers suitable for surgery.