Liver Cancer: PHYSICIANS - Percutaneous Hepatic Perfusion (PHP), Targeted Drug Delivery, Chemotherapy, Delcath Systems, Inc.,Melanoma Information Website, Metastatic, NCI, Adenocarcinoma, Hepatocellular, Neuroendocrine Clinical Trial Treatment

FOR PHYSICIANS  The Delcath System The Delcath System, or Percutaneous Hepatic Perfusion (PHP), offers a new regionalized approach for the treatment of unresectable hepatic malignancies in which the drug Melphalan is administered via the hepatic artery and the venous effluent of the liver is collected and filtered using a percutaneously placed catheter and filtration system. Benefits of the procedure include: Minimally Invasive - PHP utilizes a series of catheters and extracorporeal filters to infuse chemotherapeutic agents to tumors in the liver with minimal systemic exposure. Higher Dosing - PHP allows infusion doses exceeding those of systemic or intra-arterial administration. Repeatable Procedure - Unlike surgical isolated hepatic perfusion (IHP), which can be performed only once, PHP can be repeated several times. Patients within the trial usually receive the treatment at four-week intervals and up to ten treatments have been administered to a patient. Decreased Toxicity - Filtration of the hepatic venous effluent can reduce systemic exposure of chemotherapy by 80% to 90% compared to hepatic artery infusion alone.

> PHP Clinical Explanation

PHP uses a double balloon catheter positioned within the inferior vena cava (IVC) to isolate hepatic venous outflow and divert the blood through an extracorporeal filtration system; chemotherapy infused through a catheter positioned in the hepatic artery is filtered after the blood exits the liver, so that systemic exposure is limited. The main component of the system is a 16-F, polyethylene double balloon catheter with one large lumen and three accessory lumina.The two low-pressure occlusion balloons are inflated independently; the cephalic balloon blocks the IVC above the hepatic veins, while the caudal balloon obstructs the IVC below the hepatic veins, allowing complete isolation of hepatic venous outflow. The span between the two occlusion balloons consists of a fenestrated segment that feeds into the large central lumen, which exits the catheter from the proximal end. The additional lumen enters the catheter at a point inferior to the caudal balloon and allows some blood flow from the infrarenal IVC to the right atrium. During the procedure, up to 3 mg/kg of melphalan is infused through a catheter in the hepatic artery. The melphalan perfuses the liver and exits the organ through the hepatic veins. Hepatic venous effluent is collected using the double balloon catheter and melphalan-dosed blood from the central lumen is pumped through an extracorporeal circuit consisting of a centrifugal pump and two activated-carbon filter cartridges arranged in parallel.

The filtered blood is returned to systemic circulation via a venous return sheath inserted into the internal jugular vein. Treatments are administered with patients under local or general anesthesia and heparin is administered during the procedure.

Bilateral internal jugular veins and the right common femoral vein and artery are accessed using the Seldinger technique and ultrasound guidance. The hepatic arterial catheter is positioned in the proper hepatic artery using standard fluoroscopic and arteriographic techniques. A complete visceral angiogram is performed via both the celiac and superior mesenteric arteries, and the arterial supply to the liver is completely defined. When present, small accessory hepatic arteries and extrahepatic branches are embolized to ensure that the infused chemotherapy is administered only to the liver. The double balloon catheter is then inserted into the IVC using the Seldinger technique and is positioned under fluoroscopic guidance.

The double balloon catheter is then attached to the extracorporeal circuit tubing, and the outflow line of the filtration circuit is connected to the venous return sheath. Under fluoroscopy, the cephalad balloon is inflated and manipulated with gentle traction until indentation of the diaphragmatic hiatus is visible at the inferior margin. Under fluoroscopy the caudal balloon is inflated with dilute contrast medium until the lateral edges of the balloon deform to the walls of the IVC. Contrast medium is injected through the fenestrated portion of the catheter to ensure that the balloon catheter is properly placed and the hepatic venous outflow is isolated and without leakage into the right atrium. The filters are brought online. Melphalan is administered as a 30-minute infusion via the hepatic artery. Following infusion, the extracorporeal filtration circuit is continued for an additional 30 minutes. At completion, the balloons are deflated, and the catheters are removed. The patient is kept on bed rest and is monitored for 12 hours.

 
> Back To Top <