Phrenicoabdominal venotomy for tumor thrombectomy in dogs with adrenal neoplasia and suspected vena caval invasion.

OBJECTIVE: To describe a technique for tumor thrombectomy by phrenicoabdominal venotomy in dogs with adrenal neoplasia and suspected caval invasion and to report complications and outcomes associated with the procedure.

STUDY DESIGN: Retrospective case series.

ANIMALS: Eight client-owned dogs with invasive adrenal tumors.

METHODS: Medical records of dogs diagnosed with adrenal tumors with extension of thrombus into the phrenicoabdominal vein (PAV) and vena cava were reviewed. Cases where phrenicoabdominal venotomy without cavotomy for thrombus resection was performed were included. Data collected from the medical records included signalment, clinical signs, physical examination findings, diagnostic imaging results, preoperative laboratory testing, surgical technique, surgical and postoperative complications and outcome.

RESULTS: Phrenicoabdominal venotomy was successful in removal of vena caval thrombosis in 7 of 8 dogs. In one case, an attempt was made to remove a large vena caval thrombus through a distended PAV resulting in fragmentation of the thrombus and the need to extend the incision into the vena cava. In all dogs, complete removal of tumor thrombus was achieved. Two dogs died in the perioperative period, one from cardiopulmonary arrest and a second from bronchopneumonia and pancreatitis. The remaining 6 dogs were discharged from the hospital.

CONCLUSION: Thrombectomy through a phrenicoabdominal venotomy may obviate the need for a cavotomy in a subset of dogs with invasive adrenal neoplasia.