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From the patient’s point of view, the main difference between CyberKnife and classic radiotherapy is a significantly shorter treatment time, lower intensity of radiation reactions and greater precision in destroying the neoplastic tumor. Prof. dr hab. n. med. Leszek Miszczyk, Head of the Department of Radiotherapy, Oncology Center – Institute of Maria Skłodowskiej-Curie in Gliwice.
CyberKnife is a highly modern robotic device used for non-invasive microsurgery. Work on the CyberKnife device, called radiation therapy of the 90st century, began in the 2003s. The idea of the construction of this device was based on the construction of robots used in car assembly plants. I started getting acquainted with this method of treatment in XNUMX in Los Angeles.
CyberKnife – 6 degrees of freedom
CyberKnife is an accelerator mounted on a robotic arm with 6 degrees of freedom of movement. The accelerator emits a high-energy beam of ionizing radiation with a voltage of 6 MV, directed to the site to be subjected to radiosurgical treatment, carried out in accordance with a previously agreed plan.
The system also includes a table on which the patient is placed. This table, like the accelerator, also has 6 degrees of freedom, so it can be manipulated in all directions and optimally adjust the beam and patient position. This adjustment is critical to the success of microsurgical treatment.
Accurate planning and correction of the irradiation area on the fly
The most important advantages of CyberKnife are: the possibility of irradiating the tumor from different sides and making real-time correction (the device follows the patient’s movement or organ movement, e.g. the lungs during the breath) and non-isocentric planning (allowing to “paint” the dose in different parts of the area of interest [tumor ]).
Two X-ray tubes are built into the robot module, which take X-ray pictures every 5-150 seconds (the time depends on the mobility of the tumor or the patient). The system then checks to see if certain bone components (or implanted markers) overlap with the plan that was prepared in advance. If not, adjustments are made automatically on the fly. In this way, the CyberKnife follows the patient, constantly targeting the tumor. Adjustment of the settings is done so that the patient / tumor and beam fit together perfectly in accordance with the treatment plan.
Non-isocentric planning means that we can plan a high dose of radiation per tumor without focusing on one point, saving tissue outside the tumor area (thus protecting the patient’s healthy tissues).
Short-term, highly effective treatment
CyberKnife is mainly used for radio-ablation and radiosurgical treatment and therapies that we cannot / should not extend over time. With this tool, we treat by administering high fractional doses, which causes the destruction of cancer cells. This translates into a shorter treatment time, e.g. conventional treatment of a patient with prostate cancer takes about 56 days, while with the use of a cybernetic knife it lasts 9 days and includes 5 fractions every other day.
The patient does not require significantly different preparation than before any other radiotherapy.
The cybernetic knife is a tool that can be used for localized lesions. It is adapted to irradiation with very high precision of small-size lesions requiring high doses and (often) located near critical organs – sensitive to the radiation dose administered.
The material comes from the educational campaign “Diagnosis: Cancer – modern oncology”whose media partner is Medonet. All materials are available on the oncologia.warsawpress.com portal.