The primary treatment modality for cancer has traditionally been surgery. However, with advancements in radiation oncology, radiotherapy has become the second pillar of cancer treatment. The third pillar is medical oncology, which includes chemotherapy, targeted therapies, and immunotherapies.

Over the last 25 years, the development of interventional radiology (IR) techniques has introduced numerous new procedures for cancer management. As a result, Interventional Oncology (IO), a subspecialty of Interventional Radiology, has emerged as the fourth pillar of cancer treatment, now integrated into standard treatment algorithms.

The availability of multiple treatment modalities has raised important questions about selecting the most appropriate therapy for each patient. This underscores the necessity of multidisciplinary tumor boards in hospitals, where each cancer patient should be discussed to determine the optimal treatment plan.

What Treatments Are Included in Interventional Oncology?

Interventional Oncology is a subspecialty of Interventional Radiology, which also includes Vascular Interventional Radiology, Nonvascular Interventional Radiology, and Neurointerventional Radiology.

The first thing we need to mention is the process of taking biopsies using Interventional Radiological techniques to determine the nature, characteristics, cell type of the cancerous tissue, and some important features to be used in the cell. We perform this procedure in almost all tissues and systems of the body.

With the advancement of Interventional Oncological procedures, we apply "ablation" methods using various techniques to directly eliminate the cancerous tissue. If the tumor is smaller than 3 cm, the entire tumor tissue can be treated with highly effective ablation techniques. Additionally, in tumor treatments, drug therapies or radiation therapies can be administered through the blood vessels, and therefore, these treatments are alternative therapies that can directly lead to the elimination or reduction of the tumor tissue. These procedures include TACE, TARE, Chemosaturation, and LIOX. However, in cancer patients, palliative treatments are performed using interventional radiological techniques to address certain problems caused by cancerous tissue.

If a cancerous tissue in the liver or surrounding organs causes a blockage in the bile ducts, it can be opened using Interventional Radiological methods, and a stent can be placed in the tumor-affected area. Similar procedures can also be performed in the urinary tract, gastrointestinal system (stomach and intestines), and respiratory system, where stents can be placed in the blocked areas.

Which Types of Cancer Can Be Treated with Interventional Oncology?

Ablation techniques, especially thermal ablation techniques (such as microwave and radiofrequency), play a very important role in the treatment of hepatocellular carcinoma (HCC), the primary cancer of the liver. If the lesions are smaller than 3 cm, these techniques are applied effectively. However, if there are larger or multiple masses and no other treatment alternative is available, drug therapy is administered to the liver masses through the blood vessels. This procedure is called transarterial chemoembolization (TACE). If radiation therapy is performed during this procedure, it is called transarterial radioembolization (TARE). If there are liver metastases from malignant melanoma or chemotherapy-resistant breast cancer, chemosaturation can be applied as the most effective treatment alternative. With newly developed LIOX and similar techniques, more effective drug delivery methods to the liver and other organs are also available.

In the treatment of intrahepatic cholangiocarcinoma, one of the primary liver cancers, ablation, TACE (transarterial chemoembolization), or TARE (transarterial radioembolization) can be performed if surgery is not feasible, depending on the number and size of the lesions, similar to hepatocellular carcinoma.

The primary treatment for primary lung cancers is surgery. However, in patients who are not suitable for surgery, ablation techniques can be used. Additionally, in the treatment of lung metastases, ablation techniques and SBRT (stereotactic body radiotherapy) can be applied.

In primary kidney tumors (RCC), ablation techniques are effectively used for T1A tumors (smaller than 4 cm) and T1B tumors (smaller than 7 cm). Among these, the freezing technique (cryoablation) stands out as the most effective method.

Cryoablation is an effective treatment method for soft tissue tumors, and it is also commonly used in the treatment of bone tumors.

Additionally, interventional radiological ablative techniques are increasingly being used as a treatment alternative for benign thyroid tumors and for benign or malignant breast tumors that are not suitable for surgery.

Why Is a Multidisciplinary Approach Essential in Cancer Treatment?

Cancer treatment options vary significantly depending on the tumor type, organ involved, and histopathological characteristics. The selection and sequencing of different therapies require multidisciplinary tumor board discussions to ensure optimal decision-making.

By integrating surgical, medical, radiation, and interventional oncology approaches, patient survival and quality of life can be maximized.

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