We can help when there are no longer viable options, or minimally invasive options are favored/indicated.
What is Interventional Oncology?
In human medicine, interventional radiologists routinely work intimately with oncologists to provide innovative, minimally invasive options for their patients. A similar trend has recently begun in Veterinary medicine to provide multimodal therapies along with surgeons and oncologists forming a comprehensive oncology team for our patients. Interventional oncology can help provide minimally invasive options with low morbidity for patients who have historically had limited options.
Chemoembolization of liver tumors (TACE-transarterial chemoembolization):
Candidates:
– Animals with hepatic tumor that are not amenable to conventional surgical excision (typically HCC)
– Tumors that are progressive or at risk or have historically developed a hemoabdomen
– Dogs with limited evidence of systemic spread are preferred as candidates
Procedure:
Dual phase contrast abdominal CT is required to assess the arterial supply of the mass and help guide subsequent intervention
A small incision over the femoral artery is made to allow catheter selection of the main arteries feeding the hepatic mass
Arteries are super selected for local delivery as hepatic tumor blood supply is typically 95% arterial vs. normal liver tissue which receives most of its blood supply from the portal system
The chemotherapy is mixed with beads and contrast that are sized to allow delivery of the chemotherapy to the capillary bed of the mass under fluoroscopic guidance
These beads may also cause embolization of the mass which reduces the blood supply and causes necrosis of the mass
Uptake of chemotherapy eluding beads into the hepatic mass in a human 24 hours after transarterial chemoembolization (TACE) shows the extent of uptake directly into the mass
Post-procedural recovery:
– Dogs have a small groin incision and are kept overnight for observation and supportive care
– Most are discharged the following day
– Preliminary data (per Dr. Chick Weisse):
– Safe procedure: <10% non-target embolization
– Tumors tend to have altered architecture at recheck CT
– 30% have reduction in size, many have areas of necrosis
– Rare case of sepsis following tumor necrosis have occured
– Increased concentration of chemotherapy to the liver with significantly reduced levels systemically
– Tumors size may be reduced for subsequent surgical resection
Percutaneous transjugular stenting for caval obstructions:
– Small incision in jugular vein for caval access
– Placement of stent(s) across obstructive lesion
– Rapid resolution of signs of impaired venous drainage
Fluoroscopic image under digital substraction (DS):
A. dorsoventral projection of a contrast study indicating the location of the tumor obstructing the caudal vena cava (CaVC) with a marker catheter across the lesion and a catheter through another senosis to the right hepatic vein (HV)
B. following stent placement in the CaVC and stent placement in the CaVC through to HV. Immediate decompression of the HV and CaVC is noted as is contrast flow towards the heart.Other oncological interventions offered at ACCESS:
– Chemoembolization of non-resectable tumors
– Endoluminal stenting: urethral, ureteral, biliary, tracheal neoplasia
– Caval stenting for heart-based tumors or other cause of caval obstruction
– Intra-arterial chemotherapy: prostatic tumors, bladder tumors
– Cryoablation, thermoablation
– Endoscopic removal of tracheal masses
– Endoscopic removal of esophageal, gastric, colonic and bladder polyps
References:
1. Schlicksup MD, Weisse CW, Berent AC, Solomon JA. Use of endovascular stents in 3 dogs with Budd-Chiari syndrome. J Am Vet Med Assoc. 2009 Sep 1;235(5):544-50.
2. Guan, YS, He, Qing, Wang, MQ. Transcatheter arterial chemoembolization: history for more than 30 years. Gastroenterology Volume 2012, Article ID 480650, 8 pages
For more information, please contact our Internal Medicine Department at (310) 558-6100.
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