Transarterial chemoembolization

Metastatic melanoma that has travelled to a person's liver can be treated in a variety of ways. One form of treatment is called ‘transarterial chemoembolization’ (TACE). In general, metastatic melanoma to the liver is treated with TACE when the tumors in the liver cannot be removed with surgery.

TACE is often described as a ‘minimally invasive procedure’. That means it's done by entering the body via the skin, a body cavity or an anatomical opening. By doing so, the amount of damage done to the exterior of the body is kept to a minimum.

TACE is designed to kill a liver tumor in two ways. First of all, the proceedure involves halting the flow of blood to the tumor. Once it has done that, TACE then delivers a high dose of chemotherapy directly to the tumor and the zone immediately surrounding it.

When treating stage 4 melanoma that has metastasized to the liver, TACE offers several potential benefits. Firstly, it may overcome the limited effectiveness of whole-body chemotherapy (which doctors call ‘systemic chemotherapy’). This limited effectiveness is caused by the liver’s ability to break down systemic chemotherapy quickly.

The second potential benefit of TACE is that it seeks to avoid systemic chemotherapy’s tendency to damage healthy tissue in the liver and elsewhere in the body. This means stronger doses of chemotherapy can be given than is possible with systemic chemotherapy.

That said, when stage 4 melanoma tumors in the liver are treated with TACE, systemic chemotherapy and other forms of treatment are still often used.

How does TACE work? Firstly, thousands of tiny particles are inserted into the blood vessels in the liver that feed the tumor. These stop the flow of blood feeding the cancer. Meanwhile, the particles, which are coated with the chemotherapy drug, slowly release that drug into the tumor.

To position the particles in the liver, a thin spaghetti-like tube called a catheter is inserted into the femoral artery in the groin. This catheter is then extended to the target blood vessels. Once the catheter reaches its target, the tiny particles are injected through it and out into the blood vessels.

When the particles reach their destination in the blood vessel, they start discharging the chemotherapy drug.

Once the particles have offloaded the chemotherapy drug, they remain in place permanently.

Importantly, TACE is not regarded as a cure. Instead, it is generally seen as a palliative treatment for people with stage 4 melanoma that has metastasized to the liver.