A Minimally-invasive Approach to Liver Surgery

The typically compromised patients combined with high vascularity, difficult access, and poor suture holding all contribute to making liver surgery challenging for the veterinary surgeon. Risks can be reduced by careful planning, appropriate pre-operative patient preparation, knowledge of the anatomy and physiology, and alternative plans should they become necessary. While many solitary massive HCC tumors can be surgically excised with median survival times greater than 3 years, there is a 29% surgical complication rate and this does not include the many liver tumors defined as nodular or diffuse that are not resectable. While the surgical mortality rate was only 5% in this population of dogs, right-sided tumors were associated with a 40% mortality rate!! In addition, up to a third of dogs with massive HCC in another study were identified to have distant metastases making invasive surgery a less optimal solution. It is generally agreed that easily resectible, isolated massive left-sided (and pedunculated central and right-sided) HCC cases should receive surgical excision; this leaves a faily large proportion of HCC cases for which surgery may not be the ideal treatment. Surgical resection of these tumors is addressed in another lecture so this presentation will be limited to the discussion of alternative options for those cases in which surgical excision would be associated with excessive risk of considerable morbidity or mortality or cases in which surgery is not indicated. A number of minimally invasive options exist for use in dogs with liver tumors and liver disease. Most oft hese are still considered experimental in veterinary patients but each will be briefly discussed. These techniques include transjugular liver biopsy, stenting for malignant obstructions, local delivery of chemotherapy (intra-arterial chemotherapy), transarterial embolization (TAE) for hemorrhage or tumors, transarterial chemoembolization (TACE) with or without drug-eluting brads (DEBs), portal vein embolization (PVE), and percutaneous ablation.