Transarterial chemoembolization (TACE) is a minimally invasive, image-guided procedure primarily used to treat liver cancer, specifically hepatocellular carcinoma (HCC). TACE is a localized treatment option, meaning it limits the exposure of the rest of the body to the chemotherapy drugs, thereby reducing systemic side effects. The procedure works on the principle that liver tumors receive most of their blood supply from the hepatic artery, while the surrounding healthy liver tissue is supplied mainly by the portal vein. This anatomical difference allows for a highly focused approach to cancer treatment.
Defining the Procedure
TACE employs a dual-action mechanism to attack the tumor: targeted chemotherapy delivery and embolization. The first component involves injecting a chemotherapy drug, often mixed with an oily contrast agent like Lipiodol or loaded onto microscopic drug-eluting beads (DEBs), directly into the arteries feeding the tumor. This allows for the chemotherapy to concentrate in the tumor at levels far exceeding what is possible with traditional intravenous administration.
The second step, embolization, involves blocking the blood vessels that supply the tumor. This is achieved using the oily contrast agent, specialized beads, or other particles that physically plug the artery. Blocking the blood flow starves the tumor of oxygen and nutrients, causing it to die, a process known as ischemic necrosis. Simultaneously, the blockage traps the chemotherapy agent within the tumor, increasing the amount of time the cancer cells are exposed to the drug.
TACE is typically indicated for patients with intermediate-stage Hepatocellular Carcinoma (HCC), classified as BCLC-B, who are not candidates for curative treatments like surgery or ablation. These patients usually have preserved liver function and tumors that are multifocal but have not spread widely outside the liver or invaded the main blood vessels. The procedure is often used as a palliative treatment to control tumor growth or as a “bridging” therapy to keep tumors small while a patient waits for a liver transplant.
Performing the Treatment
Preparation for the TACE procedure involves a period of fasting and potentially recent imaging to assess the tumor’s activity and the patient’s overall health. Before the procedure begins, the patient receives intravenous sedation to help them relax and remain comfortable, though they are usually awake and able to communicate with the medical team. The medical team cleans and numbs a small area of skin, typically in the groin, which serves as the access point.
The interventional radiologist then makes a very small incision to access the femoral artery, the large blood vessel in the thigh. A thin, flexible tube called a catheter is inserted through this incision and, using real-time X-ray guidance known as fluoroscopy or angiography, is carefully threaded through the arterial network. The catheter is navigated up the aorta and selectively maneuvered into the hepatic artery, which supplies the liver, and then into the smaller branch arteries that feed the tumor itself. The radiologist injects a contrast dye to create a precise map of the tumor’s blood supply, confirming the catheter’s exact position.
Once the catheter is precisely positioned in the tumor-feeding vessel, the chemoembolic mixture—the chemotherapy drug combined with the embolic agent—is slowly injected. The entire procedure typically takes between one and three hours, depending on the number and complexity of the tumors being treated. After the injection is complete, the catheter is removed, and pressure is held on the access site in the groin for a period of time to prevent bleeding.
Immediate Post-Procedure Experience
Following the TACE procedure, the patient is moved to a recovery area for monitoring, where they must remain lying flat for several hours to allow the femoral artery access site to seal properly. Most patients are admitted for an overnight stay in the hospital, which allows the medical team to monitor for any immediate reactions and manage initial symptoms. The most common and expected reaction is a collection of symptoms known as Post-Embolization Syndrome (PES).
PES is a temporary condition that affects a large percentage of TACE patients. Symptoms typically include fever, abdominal pain or discomfort in the right upper quadrant, and nausea or vomiting. These symptoms are generally considered a normal sign that the treatment has successfully caused tissue death in the tumor, leading to the release of inflammatory mediators.
The symptoms of PES usually begin within the first 72 hours following the procedure and are self-limiting, gradually subsiding over a few days to a week. Management focuses on supportive care, utilizing intravenous fluids, and administering medications to control pain, fever, and nausea. Patients are typically discharged the day after the procedure and can expect to resume most normal daily activities within a week, though temporary fatigue and loss of appetite are common during this initial recovery period.
Monitoring and Future Outlook
The success of the TACE procedure is not measured immediately but through follow-up imaging to assess the tumor’s response to the treatment. The first detailed assessment is typically performed four to six weeks post-procedure using contrast-enhanced CT or MRI scans. This timing allows for the initial inflammatory changes to resolve, providing a clearer image of the tumor necrosis. The tumor is considered successfully treated if the imaging shows a lack of arterial enhancement, indicating that the tumor is no longer receiving blood flow and is dying.
TACE is often a sequential treatment, meaning it may need to be repeated to achieve optimal tumor control. For tumors that show partial response or new tumor growth, repeat TACE sessions may be scheduled, often every two to three months or whenever the tumor shows signs of recurrence.
The procedure may also be incorporated into a broader, multi-modal cancer treatment strategy. TACE can be combined with other local therapies like thermal ablation or with systemic treatments such as targeted therapeutic agents and immunotherapy to improve overall outcomes.