Primary liver cancer is one of the most malignant liver diseases. According to what cells make up the tumor, several types of liver cancer are distinguished. The most common of them, accounting for about 75-80 percent. cases – hepatocellular carcinoma (HCC). It is the fifth most common oncological disease, and the third cause of death from oncological disease in the world , with an overall five-year survival rate of just 18%. However, with the rapid development of medicine, new treatments are emerging that give new hope to patients with this disease. More about them is told by dr. Rokas Račkauskas, a doctor of abdominal surgery at Vilnius University Hospital Santaros Clinic (VUL SK), head of the nuclear medicine department, a radiologist, a specialist in nuclear medicine. Renata Komiagienė and dr. Marius Kurminas, radiologist, head of the interventional radiology department.
Liver cancer treatment methods
According to Dr. Roko Račkauskas, the tactics of liver cancer treatment depend on the spread of the disease, the level of cancer markers and liver function. It is also important to assess whether the patient has viral hepatitis, chronic liver or other concomitant diseases. The most common surgical methods of treatment used to cure the disease are liver resection and liver transplantation. Depending on the stage, local treatment may also be prescribed – ablation, transarteral chemoembolization, selective intra-arterial radioembolization. Local tumor treatment can also be combined with systemic – systemic chemotherapy or biological therapy. If the patient cannot undergo surgery, his inclusion in the liver transplant list is considered. In this case, in order to stop the spread of the disease and prolong the patient’s survival rate while he is waiting for the donor organ, the patient may be subjected to minimally invasive (bridge (bridge (bridging)) procedures.
“What method of treatment will be chosen for a particular patient depends on the Barcelona criteria, which are used to assess the prognosis of the disease and the result of treatment. Which minimally invasive method to choose is usually decided during an interdisciplinary discussion involving liver surgeons, radiologists, interventional radiologists, chemotherapists, gastroenterologists,” says the doctor of abdominal surgery.
Radioembolization – a personalized method of treatment that allows you to ensure the maximum effect ofanti
One of the most innovative minimally invasive liver cancer treatment methods currently used is trans-arterial radioembolization (TARE). According to R. Komiagienė, Head of the Nuclear Medicine Department of VUL SK, this method of treatment is used in cases of non-operative (not suitable for operative treatment) liver tumors and metastases to the liver. The procedure is complex and requires team concentration. Each specialist involved assesses the patient’s suitability for the procedure and the technical possibilities of its performance. Absolute contraindications to this procedure – pregnancy and sensitivity to iodocontrastic substance.
The radioembolization procedure consists of 2 stages – invasive diagnostic and treatment stage. The two steps are identical, only the amount of radioisotope injected differs. During the diagnostic phase, a small dose of a radioactive agent is injected. “This stage is needed so that we can see exactly which areas the preparation is entering, so that we can carry out a safe therapeutic procedure for the patient. To achieve the best possible effect, special software calculates the dose needed for each focus and patient. In this way, we are approaching personalized treatment, when its tactics – the dosage of the drug, localization – are selected in a personalized manner,” says the doctor radiologist R. Komiagienė.
The procedure requires one-day hospitalization in the hospital department, and the patient must arrive ready for the invasive procedure. Radioembolization is performed in the interventional radiology operating room, during which local anesthesia is applied, so the patient remains conscious, only unpleasant sensations are suppressed.
The local method of treatment affects the tumor focus from the inside
Renata Komiagienė points out that unlike systemic treatment, which affects the entire body, radioembolization is a local method of treatment, using which the maximum radiation effect is concentrated in the tumor and the surrounding liver tissue.
“To affect the tumor focus from the inside, isotopes that emit high radiation energy are used. In the case of procedures performed by VUL SK, an isotope of radioactive holmes is used (|Ho 166), which is provided in the form of plastic microspheres (microgranules). In a minimally invasive interventional procedure, holmium microspheres are deposited in the tumour tissue and the beta radiation emitted by the isotope affects the tumour biology and promotes tumour cell death. The Holmium isotope has unique properties, such as additional low-energy gamma radiation and paramagnetic radiation, which make the isotope visible in diagnostic equipment. This allows you to plan the procedure with high accuracy and calculate the dose of individually prescribed radioactivity, so that the treatment is more successful and does not have serious side effects,” says the radiologist.
According to Dr. M. Kurmin, Head of the Interventional Radiology Department of VUL SK, fast-growing liver tumors have a lot of nourishing blood vessels, it is this property that is what is being sought to be taken advantage of. “Our task is to identify those blood vessels and use special navigational angiographic programs to get into them. During treatment, we puncture the artery of the arm or thigh, enter the hepatic arteries with special guiding catheters, and with even thinner microcateters (0.6-0.8mm in diameter) we reach the arteries that feed the tumor and slowly inject radioactive particles with a stream of blood. The precisely calculated amount of particles ‘gets stuck’ in the microcracks of the tumor, internal irradiation takes place – radioactivity destroys nearby tumor cells,” he says.
After the procedure is carried out, by scanning with radiological equipment (gamma chamber), the position of the microspheres is clarified. At night after the procedure, the patient remains in the hospital to monitor the general condition. In the absence of complications, in the morning it is released home. For further treatment, the patient is usually referred to a specialist in abdominal surgery or a doctor oncologist-chemotherapist. Often, 3 months after radioembolization, radiological examination control is carried out.
The safety of the procedure is ensured by a qualified team of specialists
Speaking about the safety of this procedure, R. Komiagienė says that it does not pose a higher risk to the patient, and the possible complications are associated with the intervention of a minimally invasive procedure. Meanwhile, the frequency of complications associated with exposure is minimized during the process of dosimetry and individual planning until the introduction of a therapeutic dose of radioisotope into the tumor. In rare cases, the patient may experience nausea, vomiting, a temporary elevation of liver enzymes in the blood, neutropenia. All these side effects can be controlled by medication.
When working with open sources of radiation, it is also necessary to take care of the safety of personnel in the operating room. This, according to R. Komiagienė, is ensured by a qualified trained team of specialists. Special means of protection are used in the preparation of the isotope for the procedure and during it, in the recovery of residues, etc. For the infusion of microspheres, a special shielding system is used to provide protection to the specialists performing the procedure.
“Radioembolization is one of the types of local therapy, as of 2022. included in international liver cancer treatment guides. This procedure in our country is reimbursed by the budget of the Compulsory Health Insurance. By a similar principle, we have been performing TACE (transarteric chemoembolization) for more than 12 years, only in this case the allowed particles are saturated with chemopreparations – this is how the tumor tissue reaches a much higher concentration of the drug, avoiding systemic effects. Thus, we are destroying non-surgical liver cancer without impairing the patient’s quality of life. Another good news for patients with hepatocellular carcinoma is that these methods of local therapy can also be applied against the background of systemic chemotherapy,” dr. Marius Kurmin points out at the end of the conversation.
