Hepatic arterial infusion | |
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Specialty | oncology |
Hepatic arterial infusion (HAI) is a medical procedure that delivers chemotherapy directly to the liver. The procedure, mostly used in combination with systemic chemotherapy, plays a role in the treatment of liver metastases in patients with colorectal cancer (CRC). [1] Although surgical resection remains the standard of care for these liver metastases, majority of patients have lesions that are unresectable.
The liver derives its blood supply from two sources – via the hepatic arterial circulation and the portal circulation. Liver metastases get most of their blood supply primarily from the hepatic artery, whereas the normal liver cells get their blood supply from the portal circulation. [2] This allows for chemotherapeutic drugs to be delivered directly to the cancer cells if infused into the hepatic artery. Multiple trials have compared HAI (with various chemotherapeutic agents) to systemic chemotherapy. Compared to systemic Fluoropyrimidine, HAI with Floxuridine (FUDR) had an increased response, but there was no overall increase in patient survival. [3] [4] [5] [6] [7] Efforts have been made to increase the efficacy and safety of HAI chemotherapy: when a combination of FUDR and dexamethasone was used for HAI, both response rate and median survival increased. [8] In another study, a combination of FUDR and leucovorin for HAI increased the response rate, and reduced the biliary toxicity seen with the use of FUDR alone. [9] Considering improvements in the surgical placement of the HAI pump and studies showing promising results when HAI therapy is used together with systemic oxaliplatin or irinotecan, [10] [11] there is once again an increased interest in the role of HAI as a treatment option in patients with cancer, who have unresectable CRC liver metastases. However, studies recommend that this treatment modality be restricted to centers with expertise in the surgical placement of these pumps, and the technical aspects of localized chemotherapy.
Before the placement of the HAI pump, the patients undergo an arteriogram to outline the blood supply of the liver and to identify any anatomical anomalies. The procedure begins with an exploratory laparotomy to confirm the unresectable nature of the tumor, and then the gallbladder is removed by performing a cholecystectomy. This is done to prevent treatment induced cholecystitis. The distal gastroduodenal artery, the right gastric artery, and small branches supplying the stomach and duodenum are ligated. This total devascularization of the distal stomach and proximal duodenum minimizes the risk of any extra hepatic perfusion. [12] The catheter is placed at the junction of the proper and common hepatic arteries, and threaded through the gastroduodenal (mostly), or celiac artery. The catheter is fixed in this position and the pump is placed in a subcutaneous pocket. Finally, to confirm adequate placement and hepatic perfusion, and to rule out extrahepatic perfusion, a dye (fluorescein or methylene blue) is injected into the pump. After the procedure and before starting the HAI based treatment, a technetium 99m-labeled macroaggregated albumin scan is performed to again confirm adequate hepatic perfusion and no misperfusion outside of the liver. [13]
The complications of HAI therapy can be divided into those related to the surgical placement of the pump, technical catheter-related complications, and those related to the chemotherapeutic agents used.[ citation needed ]
Relating to the surgical HAI pump placement, early postoperative complications consist of arterial injury leading to hepatic artery thrombosis, inadequate perfusion of the entire liver due to the inability to identify an accessory hepatic artery, extrahepatic perfusion to the stomach or duodenum, or hematoma formation in the subcutaneous pump pocket. Late complications are more common and include inflammation or ulceration of the stomach or duodenum, and pump pocket infection.[ citation needed ]
The most common catheter related complications include displacement of the catheter, occlusion of the hepatic artery because of the catheter, and catheter thrombosis. [13] These catheter related complications don't occur as frequently with increased surgical experience and with improvements in pump design. [14]
The most common toxicities caused by the chemotherapeutic agents were gastrointestinal symptoms, chemical hepatitis, and bone marrow inhibition. [14] It is important to note that the most serious and dose limiting complication of HAI is hepatobiliary toxicity. This occurs more commonly with FUDR than any other chemotherapeutic agent. [15] Patients undergoing HAI therapy therefore have regular liver function tests to monitor any damage to the liver. As previously mentioned, studies have been carried out to come up with treatment algorithms to minimize this serious side effect. It has been shown that adding leucovorin and FUDR for infusion through the pump not only reduces the biliary toxicity of the drug, but also increases the response rate. [9] However, biliary sclerosis is not seen with HAI using 5-FU. [16] 5-FU is associated with an increased risk of myelosuppression. Logically, it would make sense to therefore consider alternating between HAI FUDR and HAI 5-FU.[ citation needed ]
Hepatocellular carcinoma (HCC) is the most common type of primary liver cancer in adults and is currently the most common cause of death in people with cirrhosis. HCC is the third leading cause of cancer-related deaths worldwide.
Interventional radiology (IR) is a medical specialty that performs various minimally-invasive procedures using medical imaging guidance, such as x-ray fluoroscopy, computed tomography, magnetic resonance imaging, or ultrasound. IR performs both diagnostic and therapeutic procedures through very small incisions or body orifices. Diagnostic IR procedures are those intended to help make a diagnosis or guide further medical treatment, and include image-guided biopsy of a tumor or injection of an imaging contrast agent into a hollow structure, such as a blood vessel or a duct. By contrast, therapeutic IR procedures provide direct treatment—they include catheter-based medicine delivery, medical device placement, and angioplasty of narrowed structures.
A pancreaticoduodenectomy, also known as a Whipple procedure, is a major surgical operation most often performed to remove cancerous tumours from the head of the pancreas. It is also used for the treatment of pancreatic or duodenal trauma, or chronic pancreatitis. Due to the shared blood supply of organs in the proximal gastrointestinal system, surgical removal of the head of the pancreas also necessitates removal of the duodenum, proximal jejunum, gallbladder, and, occasionally, part of the stomach.
Transcatheter arterial chemoembolization (TACE) is a minimally invasive procedure performed in interventional radiology to restrict a tumor's blood supply. Small embolic particles coated with chemotherapeutic drugs are injected selectively through a catheter into an artery directly supplying the tumor. These particles both block the blood supply and induce cytotoxicity, attacking the tumor in several ways.
Floxuridine is an oncology drug that belongs to the class known as antimetabolites. Specifically, floxuridine is a pyrimidine analog, classified as a deoxyuridine. The drug is usually administered via an artery, and most often used in the treatment of colorectal cancer. The quality of life and survival rates of individuals that receive continuous hepatic artery infusion of floxuridine for colorectal cancer metastases is significantly higher than control groups. Floxuridine can also be prescribed for the treatment of kidney and stomach cancers. In vitro uses of floxuridine include 5-minute treatments of fluorouracil, floxuridine, and mitomycin to increase cell proliferation in Tenon's capsule fibroblasts.
Hepatectomy is the surgical resection of the liver. While the term is often employed for the removal of the liver from a liver transplant donor, this article will focus on partial resections of hepatic tissue and hepatoportoenterostomy.
Sirtex Medical Limited is a medical device company, providing a radioactive treatment for inoperable liver cancer called SIR-Spheres microspheres. Sirtex was established in 1997 in Australia and currently maintains offices and manufacturing facilities in the U.S., Australia, Germany and Singapore. Following an acquisition by China Grand Pharmaceutical and CDH Genetech, Sirtex de-listed from the Australian Securities Exchange (ASX:SRX) on Monday, September 24, 2018.
Percutaneous hepatic perfusion (PHP) is a regionalized, minimally-invasive approach to cancer treatment currently undergoing Phase II and Phase III clinical testing. PHP treats a variety of hepatic tumors by isolating the liver and exposing the organ to high-dose chemotherapy. As demonstrated in clinical trials, patients treated by PHP can tolerate much higher doses of chemotherapeutic agents than those receiving traditional systemic chemotherapy without increased toxicities.
Delcath Systems, Inc. is a publicly traded specialty pharmaceutical and medical device company that develops percutaneous perfusion technologies for the targeted administration of high-dose chemotherapeutic agents to specific organs or regions of the body. Based in Queensbury, New York, the company has an intellectual property portfolio consisting of 28 patents worldwide. Delcath's Percutaneous Hepatic Perfusion (PHP) is currently undergoing Phase II and Phase III trials against tumors in the liver. Delcath has a Cooperative Research and Development Agreement (CRADA) with the National Cancer Institute and has received Fast Track and a Special Protocol Assessment from the Food and Drug Administration for its use of melphalan in treating unresectable liver tumors. PHP, also known as the Delcath System, is tested for the treatment of metastatic melanoma in the liver and for primary liver cancer and metastatic hepatic malignancies from neuroendocrine cancers and adenocarcinomas, as well as patients with melanoma who previously received isolated perfusion. Chemotherapy is usually delivered intravenously, although a number of agents can be administered orally.
The hepatic lymph nodes consist of the following groups:
A liver metastasis is a malignant tumor in the liver that has spread from another organ affected by cancer. The liver is a common site for metastatic disease because of its rich, dual blood supply. Metastatic tumors in the liver are 20 times more common than primary tumors. In 50% of all cases the primary tumor is of the gastrointestinal tract; other common sites include the breast, ovaries, bronchus and kidney.
Selective internal radiation therapy (SIRT), also known as transarterial radioembolization (TARE), radioembolization or intra-arterial microbrachytherapy is a form of radiation therapy used in interventional radiology to treat cancer. It is generally for selected patients with surgically unresectable cancers, especially hepatocellular carcinoma or metastasis to the liver. The treatment involves injecting tiny microspheres of radioactive material into the arteries that supply the tumor, where the spheres lodge in the small vessels of the tumor. Because this treatment combines radiotherapy with embolization, it is also called radioembolization. The chemotherapeutic analogue is called chemoembolization, of which transcatheter arterial chemoembolization (TACE) is the usual form.
In oncology, metastasectomy is the surgical removal of metastases, which are secondary cancerous growths that have spread from cancer originating in another organ in the body.
Intraperitoneal hyperthermic chemoperfusion is a type of hyperthermia therapy used in combination with surgery in the treatment of advanced abdominal cancers. In this procedure, warmed anti-cancer medications are infused and circulated in the peritoneal cavity (abdomen) for a short period of time. The chemotherapeutic agents generally infused during IPHC are mitomycin-C and cisplatin.
Yehuda Patt is a liver cancer specialist, gastrointestinal oncologist, and Professor of Medicine at the University of New Mexico, and resides in Santa Fe, New Mexico. He was previously at the University of Texas, MD Anderson Cancer Center between the years 1975- 2003. He is the author of various papers pertaining to cancer and their effects on people, and has been cited numerous times for his writings and analyses.
Hepatic artery embolization, also known as trans-arterial embolization (TAE), is one of the several therapeutic methods to treat primary liver tumors or metastases to the liver. The embolization therapy can reduce the size of the tumor, and decrease the tumor's impact such its hormone production, effectively decreasing symptoms. The treatment was initially developed in the early 1970s. The several types of hepatic artery treatments are based on the observation that tumor cells get nearly all their nutrients from the hepatic artery, while the normal cells of the liver get about 70-80 percent of their nutrients and 50% their oxygen supply from the portal vein, and thus can survive with the hepatic artery effectively blocked. In practice, hepatic artery embolization occludes the blood flow to the tumors, achieving significant tumor shrinkage in over 80% of people. Shrinkage rates vary.
Interventional oncology is a subspecialty field of interventional radiology that deals with the diagnosis and treatment of cancer and cancer-related problems using targeted minimally invasive procedures performed under image guidance. Interventional oncology has developed to a separate pillar of modern oncology and it employs X-ray, ultrasound, computed tomography (CT) or magnetic resonance imaging (MRI) to help guide miniaturized instruments to allow targeted and precise treatment of solid tumours located in various organs of the human body, including but not limited to the liver, kidneys, lungs, and bones. Interventional oncology treatments are routinely carried out by interventional radiologists in appropriate settings and facilities.
Radiation lobectomy is a form of radiation therapy used in interventional radiology to treat liver cancer. It is performed in patients that would be surgical candidates for resection, but cannot undergo surgery due to insufficient remaining liver tissue. It consists of injecting small radioactive beads loaded with yttrium-90 into the hepatic artery feeding the hepatic lobe in which the tumor is located. This is done with the intent of inducing growth in the contralateral hepatic lobe, not dissimilarly from portal vein embolization (PVE).
Transarterial bland embolization is a catheter-based tumor treatment of the liver. In this procedure, a variety of embolizing agents can be delivered through the tumor’s feeding artery in order to completely occlude the tumor’s blood supply. The anti-tumor effects are solely based on tumor ischemia and infarction of tumor tissue, as no chemotherapeutic agents are administered. The rationale for the use of bland embolization for hepatocellular carcinoma(HCC) and/or other hyper-vascular tumors is based on the fact that normal liver receives a dual blood supply from the hepatic artery (25%) and the portal vein (75%). As the tumor grows, it becomes increasingly dependent on the hepatic artery for blood supply. Once a tumor nodule reaches a diameter of 2 cm or more, most of the blood supply is derived from the hepatic artery. Therefore, bland embolization and transarterial chemoembolization (TACE) consist of the selective angiographic occlusion of the tumor arterial blood supply with a variety of embolizing agents, with or without the precedence of local chemotherapy infusion. The occlusion by embolic particles results in tumor hypoxia and necrosis, without affecting the normal hepatic parenchyma.
Liver angiosarcoma also known as angiosarcoma of the liver or hepatic angiosarcoma is a rare and rapidly fatal cancer arising from endothelial that line the blood vessels of the liver. It is a type of angiosarcoma. Although very rare with around 200 cases diagnosed each year, it is still considered the third most common primary liver cancer, making up around 2% of all primary liver cancers. Liver angiosarcoma can be primary, meaning it arose in the liver, or secondary, meaning the angiosarcoma arose elsewhere and metastasized to the liver. This article covers PHA, however much is also applicable to secondary tumors.
This article incorporates public domain material from the U.S. National Cancer Institute document: "Dictionary of Cancer Terms".