Chemoembolization is a percutaneous method of treating non-resectable liver tumors. It combines transcatheter embolization of hepatic arterial supply to a tumor with simultaneous infusion of concentrated chemotherapeutic agents. The majority of normal liver tissue receives blood supply from the portal vein; tumor blood supply is from the hepatic artery. Embolization blocks blood supply causing the tumor to become ischemic and necrose. A theoretical advantage of chemoembolization is that it increases the concentration and the dwell time of the drug in the tumor. Embolization results in ischemia that paralyzes cell membrane pumps that ejects drug from tumor cell. Hypoxia increases intracellular drug uptake. Retention of drug in the liver minimizes systemic symptoms and toxicity. Liver tumors most amenable to this treatment are hepatocellular carcinoma (HCC), metastasis from colorectal cancer, neuroendocrine tumors, ocular melanomas and gastric sarcomas. However, small numbers of other tumor types have been treated. Pre-procedure imaging by CT scan, MRI or ultrasound delineates the size and extent of the tumor and confirms adequate portal vein flow. Laboratory studies confirm adequate liver, coagulation and renal function prior to the procedure. Tumor markers may be evaluated to determine post procedure response.
How The Test Is Performed
The patient is admitted to the hospital the day of the procedure. Hydration, prophylactic intravenous antibiotics, anti-emetics, and anti-inflammatory medications are administered. The patient is brought to the angiography suite and under conscious sedation the interventional radiologists performs an arteriogram which demonstrates hepatic arterial anatomy, identifies blood supply to the tumor and evaluates portal vein flow. Selective arteriography of the vessels supplying the tumor allows direct infusion of chemotherapeutic agents mixed with ethiodol (an iodized oil that is selectively retained in hypervascular hepatic tumors) and polyvinyl alcohol particles. These act to occlude the artery feeding the tumor. Patients are then returned to their room and monitored closely; antibiotics, anti-emetics, and intravenous fluids are continued up to 24 hours. Most patients are released after 24 hours. Post embolization syndromeŚlow-grade fever, malaise and abdominal pain occurs in approximately 60% of patients.
Nothing to eat or drink after midnight the day prior to the procedure.
Inform The Technologist If:
Allergic to contrast media dye (IVP dye) or any evidence of kidney disfunction.
Procedure usually takes one hour to perform.
After Your Exam:
Patients are monitored in the hospital overnight and usually released by noon the following day. Follow up CAT scan or other imaging is usually performed at one month post procedure.