Since February, patients at the Complex Cancer Center undergo radiation therapy using advanced equipment, which lets reduce the treatment time.
The installed linear accelerators are characterized by increased geometric accuracy, automation of the movement of individual components of the accelerator, intuitive controls and are equipped with additional visualization systems. In particular, due to more targeted irradiation of tumor foci, it is possible to deliver a larger dose of radiation during one visit than before. This reduces the overall exposure time. For example, for diseases that were previously treated within 2-3 weeks, treatment can be completed within 3-5 visits.
Another highly appreciated advantage of modern devices is the introduction of new methods of irradiation, such as synchronizing the course of irradiation with the respiratory movements of the patient – irradiation with deep inhalation. “We use this technique, especially in women with breast cancer, because it reduces the load on the heart. This is one of the common side effects of radiation therapy for this type of cancer. Breast cancer treatment is currently very successful, and the use of this technology further improves the quality of life of patients after treatment, ”says Yana Prausova, MD, head of the Charles University Department of Oncology.
New scheduling systems also allow reconstructing the movement of tumors during respiration (4D imaging). Doctors can better evaluate tumor movement and consider it when planning radiation exposure. This is especially true in the treatment of lung tumors.
The installation of modern linear accelerators allowed the introduction of a special rotating irradiation technique (VMAT – Volume-Modulated Arc Therapy). The accelerator lever rotates around the patient, while changing the movement of the multi-plate collimator slat (sights), the rotation speed of the lever and the dose rate. This method improves the distribution of the radiation dose in the patient’s body, increasing the effect on the tumor, and at the same time, the radiation doses of the surrounding healthy tissues are significantly reduced. This is especially important when using high doses, which can be a source of adverse drug reactions.
A significant advantage for patients is the above mentioned reduction in exposure time. Previously, if one exposure lasted 10-20 minutes, now it can be done in a few minutes. At the same time, there is a significant improvement in connection with the fact that the devices are equipped with Image Controlled Radiotherapy Systems (IGRT). In practice, this means that patients undergo computed tomography directly on the lounger before each exposure and the settings are adjusted to achieve maximum aiming accuracy.
Thanks to modern linear accelerators, doctors can constantly adjust exposure plans depending on changes in the patient’s body during exposure (adaptive radiation therapy). This trend is increasingly being used, for example, in the treatment of neck tumors. Last but not least, these systems are characterized by the best processing of all imaging methods (CT, magnetic resonance imaging, positron emission tomography). Thus, doctors have the maximum information for specific patients in order to prepare the best exposure plan.
The system of verification and planning of radiation therapy, as well as all three linear accelerators were manufactured in the USA (Varian). Delivery and installation was carried out by the domestic company Amedis. The total investment reached nearly 260 million crown. The installation of new devices and planning systems is an important step in improving the quality of cancer treatment at the Complex Cancer Center. Thanks to the new accelerators, the center is one of the most equipped radiotherapy centers in the Czech Republic.