Over the past 20 years, advancements in technology, genetics, and medical sciences have progressed at a dizzying pace. The reflections of these developments in oncology have also led to promising results. Today, cancer is treated not only with traditional methods such as drug therapy, surgery, and radiotherapy but also with interventional radiological techniques.

Drug Therapy in Cancer

Drug therapy is a fundamental treatment in cancer and can be examined under several categories. The first developed and still indispensable option for many cancer types is cytotoxic therapy (which kills cancer cells), known as chemotherapy. For cancers sensitive to chemotherapy (such as breast, lung, colon, stomach, and bladder cancers), chemotherapy plays a significant role both in preventive treatment and in palliative care (used to support patients with metastatic disease, improve quality of life, and extend survival). Standard chemotherapy can save the lives of many cancer patients.

What Are the Side Effects of Chemotherapy?

While chemotherapy provides benefits, its biggest concern is its potential side effects. Chemotherapy is administered directly into the bloodstream, where it spreads throughout the body and targets tumor cells, killing harmful cells. However, at the same time, it can have destructive effects on rapidly dividing healthy cells, leading to unwanted side effects such as hair loss, nausea, anemia, weakened immunity, severe infections, and fever. The fear of these side effects concerns both doctors and patients, sometimes leading them to avoid life-saving chemotherapy.

What is Metastasis?

During tumor formation, cancer cells acquire an invasive characteristic, spreading through blood and lymphatic vessels. Cancer can lodge itself in various organs while still in the early cellular stage and remain dormant until it finds suitable conditions to grow into a separate cancerous mass, forming metastases. Each type of cancer has a different propensity and pattern for spreading.

For example, breast cancer frequently metastasizes to the bones, lymph nodes, liver, and brain, whereas melanoma (a type of skin cancer) tends to metastasize to the liver. This phenomenon is referred to as metastasis biology, and the underlying mechanisms are not yet fully understood. Regardless of the cancer type, liver metastases generally indicate a poorer prognosis.

What Causes Liver Metastases?

The liver has a unique blood supply compared to other organs. While most organs have only an artery and a vein, the liver receives blood from three sources: The hepatic artery, which brings oxygenated blood from the heart to nourish the liver cells; the hepatic vein, which carries deoxygenated blood away from the liver; the portal vein, which transports nutrient-rich blood from the digestive system to be processed in the liver.

This triple vascular system makes the liver biologically distinct and has intrigued scientists, leading to the development of specialized treatments.

Treatment of Liver Metastases

When cancer spreads to the liver, treatment options include: Surgery (if the disease is confined to the liver); local ablative (destructive) treatments using interventional radiology; liver transplantation (only in a small number of cases). For most cancers, these options are not effective, leaving chemotherapy as the only available treatment.

In the last 20 years, many interventional radiology procedures have been introduced for treating primary and metastatic liver cancers. One commonly used technique is thermal ablation, which destroys tumor tissue using microwave or radiofrequency energy.

When widespread liver tumors are present and cannot be treated with ablation, catheters inserted through the groin deliver chemotherapy directly into the liver. However, when these methods prove ineffective—especially in malignant melanoma liver metastases and some breast cancer metastases—a new technique called chemosaturation has been developed.

What is Chemosaturation?

Chemosaturation is based on the principle of isolating the liver's blood flow from the body's general circulation for a limited period. Immediately after this isolation, a catheter delivers a customized dose of chemotherapy directly into the liver vessels.

For a specific period, the chemotherapy remains circulating only within the liver. Once this safe period ends, a dialysis-like machine filters out the chemotherapy from the blood exiting the liver. The cleansed blood is then returned to the body, preventing systemic exposure to chemotherapy.

This approach maximizes chemotherapy's effectiveness on the liver tumor while avoiding the severe side effects of systemic chemotherapy.

How is Chemosaturation Performed?

Chemosaturation is a team-based procedure involving: Interventional radiology, medical oncology and anesthesiology. Each specialist plays a critical role in the procedure’s success. The process is conducted under general anesthesia. During the procedure, anesthesiologists monitor blood pressure, heart rate, and vascular flow to ensure stability.

Interventional radiologists carefully place catheters in the liver’s blood vessels to isolate its circulation. This step is crucial for patient safety, preserving vascular integrity, and avoiding liver damage. Once blood flow is isolated, chemotherapy infusion begins.

The chemotherapy drugs used in chemosaturation have a short shelf-life and must be prepared and administered precisely on time for the procedure to be effective. After the process is completed, medical oncologists oversee patient follow-up.

Which Cancers Can Be Treated with Chemosaturation?

Chemosaturation is increasingly used for, melanoma-type tumors, primary liver tumors, some types of breast cancer.

It can be applied both as an additional therapy alongside existing treatments and as a standalone treatment. Studies are ongoing to explore its benefits when combined with immunotherapy, which enhances the body’s immune response against cancer.

Chemosaturation is a highly specialized procedure that must be performed in experienced centers with a well-coordinated team. It represents a promising alternative for certain cancer patients.

Professor Okan Akhan, MD.
Head of Radiology Department, Bayındır Söğütözü Hospital

Assoc. Professor Ece Esin, MD.
Head of Medical Oncology Department, Bayındır Söğütözü Hospital