Treatments & Therapies

Transarterial chemoembolization – treatment, effect and risks

Transarterielle Chemoembolisation

In radiology , transarterial chemoembolization ( TACE ) is a minimally invasive procedure used to treat inoperable liver cancer . In most cases, it can no longer cure the liver carcinoma. However, it contributes to the prolongation of the patient’s life.

What is transarterial chemoembolization?

Transarterial chemoembolization (TACE) can be used to treat inoperable liver carcinomas (HCC) in a minimally invasive manner. The method is also suitable for the therapy of liver metastases from other carcinomas, such as neuroendocrine tumors in particular.

The term “transarterial chemoembolization” already indicates how this procedure works. The arteries supplying the cancer are temporarily blocked (embolization) with small particles to slow the blood flow. At the same time, the carcinoma is treated with targeted chemotherapeutic agents. Both the lack of oxygen caused by the embolization and the targeted injection of chemotherapeutic agents are intended to kill the cancer.

As a rule, however, liver carcinoma can no longer be cured because it usually develops in a liver that is already severely affected by cirrhosis . Healing is only successful in the rare cases in which there are only a few small nodules. In the vast majority of cases, however, this treatment is of palliative importance. It serves to prolong life. Furthermore, transarterial chemoembolization can also be used as a bridge therapy until successful liver transplantation.

Function, effect & goals

Transarterial chemoembolization is only used for primary liver carcinomas or metastases in the liver. This exploits the fact that hepatocellular carcinomas are almost exclusively supplied by small arterial vessels.

A healthy liver is nourished 75 percent from the portal vein and 25 percent from the hepatic artery. However, hepatic carcinomas and metastases in the liver are decoupled from the portal vein. 95 percent of them are supplied via the hepatic artery. This occurs via small arterial vessels that branch off from the hepatic artery. Within these arterial blood vessels, the aim of TACE is to temporarily stop the flow of blood by blocking it while the chemotherapy drug is taking effect. In order to achieve this, a so-called probing catheter is placed in the groin artery ( Arteria femoralis ) at the outlet to the liver supply.

Contrast media can be used to visualize the tumor and the position of the catheter tip. A catheter is then pushed into the hepatic artery via the probing catheter and placed in the correct position in relation to the tumour. The closer the catheter is to the carcinoma, the better it can be treated. Closer positioning allows for more aggressive local chemotherapy. There are also catheters that can be pushed deeper into the small arteries that supply the tumor. If the catheter is placed too far from the tumor, there is a risk that it will also cut off the blood supply to the pancreas or small intestineis interrupted. Today there are still no generally applicable standards with regard to the choice of embolic products and chemotherapeutic agents.

Lipiodol® or spherical gelatine or plastic particles are often used as embolic products. Lipiodol® is an iodine-containing oily liquid that temporarily blocks the blood vessels by forming droplets. Both the oil droplets and the plastic or gelatin particles can slow blood flow. The tumor is undersupplied with oxygen. At the same time, the chemotherapeutic agent is injected through the catheter. The main chemotherapeutic agents used are mitomycin C , carboplatin and doxorubicin .

After this treatment, another embolization takes place. Transarterial chemoembolization usually consists of a combination of embolization and chemotherapy. In individual cases, embolization is also performed without chemotherapy or local chemotherapy without embolization. However, the best long-term successes were achieved by combining both methods. It is recommended to repeat the TACE treatment several times, depending on the success of the therapy, in order to fight as many cancer cells as possible. Studies have shown that the two-year survival rate increases significantly compared to untreated patients.

For significantly more of those affected, there is the chance of having a liver transplant carried out for complete healing by extending the bridging time. Alternatively, TACE can also be combined with other therapy methods. These include percutaneous ethanol injection therapy (PEI), radiofrequency ablation (RFA), selective internal radiotherapy (SIRT) or sorafenib chemotherapy. In percutaneous ethanol injection therapy, a 95 percent ethanol solution is injected through the skin into the tumor. Radiofrequency ablation works with an applicator inserted into the tissue, which destroys the diseased tissue by generating heat.

The chemotherapeutic agent sorafenib is administered orally in the form of tablets. These procedures can be used in conjunction with embolization. The SIRT procedure uses beads provided with radioactive yttrium, which both destroy the tumor through radiation and at the same time have an embolizing effect.

Risks, side effects & dangers

However, there are also contraindications for transarterial chemoembolization. This procedure must not be used in the case of a pedunculated tumor type, blood coagulation disorders , allergies to the contrast medium, cardiac insufficiency or severe cardiac arrhythmias .

TACE is also contraindicated in the case of severe tumor infestation of the liver or tumor infiltration into the hepatic veins, the portal vein and neighboring organs. Of course, this also applies to severe liver failure or a poor general condition. It must also be emphasized that the success of the procedure depends on the stage of the disease. The more tumor foci there are, the more complex the treatment becomes. Some cases represent borderline cases in which it is often difficult to decide whether a treatment is still effective or even counterproductive.

Lisa Newlon
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Hello! I am Lisa Newlon, and I am a medical writer and researcher with over 10 years of experience in the healthcare industry. I have a Master’s degree in Medicine, and my deep understanding of medical terminology, practices, and procedures has made me a trusted source of information in the medical world.