THE TRUEBEAM DEVICE, WHICH HAS BEEN USED IN TURKEY AND THE REST OF THE WORLD FOR THE LAST FEW YEARS AND IN WHICH ALL TECHNOLOGIES UTILIZED IN RADIATION ONCOLOGY ARE COMBINED, MAKES IT POSSIBLE FOR RADIOTHERAPY TO BE APPLIED TO CANCEROUS TUMORS IN MANY PARTS OF THE BODY WITHOUT HARMING THE SURROUNDING TISSUES.
Radiotherapy is utilized during some stage of the treatment in 65% of all cancer cases. When the correct target location is determined and the correct dose of energy is transferred to this location, cellular damage is achieved in the target; in other words, cancerous cells in the target spot are destroyed. Since this procedure is very similar to removal of a tumor with open surgery, application of radiation on a single spot through radiotherapy is referred to as “radiosurgery”. Associate Professor Meriç Şengöz, a radiation oncologist at Acıbadem Kozyatağı Hospital, says, “This method involves application of a dose which is as effective as a knife while minimizing the damage to the area surrounding application and destroying the target completely. Conventional surgery requires removal of tumors from the body; however, radiosurgery simply consists of the elimination of such tumors where they are located and without making any incisions”. This type of treatment method needs a correct diagnosis, a suitable patient, a detailed information process and a very good imaging procedure to be applied. Associate Professor Şengöz says, “We need to be very clear on the exact location of the target, as well as its boundaries. We determine the patient’s position and the manner in which we will keep them in place depending on this information. If there are any organs that may move despite all the measures, it becomes necessary for us to hit the target despite such an organ’s presence. Therefore, the frequency of imaging has to be very high and we have to confirm the position and try to irradiate the necessary spot by ensuring synchronization with the movements of the organ in question. In order to achieve this, infrastructural and technological support is required. The TrueBeam device, which is a new generation radiotherapy system, has properties that provide a solution for all these considerations”.
THE DEVICE IS USED ON SPECIFIC TUMORS
The stereotactic body radiation therapy applied via the TrueBeam device can be used for lungs, head and neck region or any metastasis which is not too big and is located in the inner part of the spine, as well as some tumors in the liver, which is another moving organ, and the tumors in the suprarenal glands and pancreas. Associate Professor Şengöz states that prostate, bone tumors and soft tissue sarcomas in any part of the body can also be treated with radiotherapy via this method.
PREFERABLE FOR PATIENTS WHO ARE TREATED SURGICALLY
Radiosurgery is referred to as stereotactic radiotherapy (SRT) when used for treatment of the lesions in the brain, and stereotactic body radiation therapy (SBRT) when used for treatment of the lesions in the rest of the body. TrueBeam has both these technologies combined in a single device. Associate Professor Şengöz states that stereotactic radiotherapy has been applied to brain tumors for a long time and that TrueBeam has recently brought stereotactic body radiation therapy to the foreground as well. Şengöz says, “The first scenario that comes to mind with this method is lung cancer. The lung is a moving organ and lung cancer is a risky disease. It is critically important for tumors in the lung to be eliminated. Those of us at this profession encounter advanced stages of this disease quite frequently and conventional surgery can be inevitable for these. However, surgery is not possible for some of the advanced cases. Radiotherapy, on the other hand, has a larger area of application and does not require precise technology. The increase in the public awareness, as well as the development of advanced imaging methods, has also made it possible for early nodules and initial stages of lung cancer to be detected in a small group of cases. Apart from these cases, TrueBeam stereotactic body radiotherapy presents an advantageous method to those who do not want surgery, as well as those who are not suitable for it. In addition to early stage primary tumors in the lungs, lung metastasis nodules can also be irradiated with TrueBeam”.
SELECTION OF SUITABLE PATIENTS
Associate Professor Meriç Şengöz states that treatment with TrueBeam requires for the patient to be suitable for local therapies other than surgery, which means that the patient should not need systemic treatment (chemotherapy-medication) and be evaluated as completely treatable with local treatment. Associate Professor Şengöz says, “In such a case, one of the treatment alternatives is radiosurgery. We are not there yet, but in years to come, we will be asking the patient whether s/he prefers conventional surgery or radiosurgery even if s/he is suitable for conventional surgery. I believe that, when radiosurgery becomes more commonly utilized and standardized, advanced phase results for radiotherapy will be equal to those of conventional surgery in some cases and even better than those of conventional surgery in other cases. Radiosurgery is also useful when the disease relapses or some parts of the tumor are failed to be removed during conventional surgery and it is not considered for a second operation to be performed”.
A HIGHER NUMBER OF ADVANTAGES FOR PATIENTS
The application through stereotactic body radiation therapy with TrueBeam is easier to be tolerated by the patient because the procedure is completed in a much shorter time. While standard treatment methods involve procedures that last even longer than a month, it is possible for everything to be completed within five days at most when it comes to radiotherapy.
PLEASING TREATMENT RESULTS
Stereotactic body radiation therapy with TrueBeam also increases the chance of using high radiation doses. Associate Professor Şengöz says, “The teachings of treatment with radiation indicate that there is not a single living being that cannot be destroyed with radiation. This generally depends on the dosage, as well as the dimensions of the application area. Since TrueBeam application involves irradiation of a very limited area with a very high dose, tumors are taken under control in an earlier period or at a higher rate. We are very pleased with the early phase results of the applications carried out in our hospital. The applications in some external institutions that have been using the method for a long time have also begun to bear fruit”.
MAINTAINING THE CORRECT POSITION IS ESSENTIAL
There are important differences between application of radiosurgery in the brain and application of it on any other part of the body. Associate Professor Meriç Şengöz states that procedures on the brain involve usage of a mask or immobilization of the head with a frame in order to prevent losing the location of the tumor and says, “When it comes to radiosurgery on the body, it is necessary to constantly check whether the patient is still lying in the same position. TrueBeam, makes it possible for this to be ensured via the cameras and reflectors placed on the body, as well as enabling for all movements of the patient, including respiration, to be monitored without losing much time. It also enables us to have a three-dimensional image of the tumorous structure and differentiate between its present and former states. This treatment causes the tumor to undergo the change it would have undergone in 25 days with standard treatment in only 3 or 4 days. The system that provides table movements in six different directions, which is used together with TrueBeam, makes it possible for us to adjust the position of the patient very precisely by simply pushing a button and not even having to move ourselves”.