Radiation therapy planning
Obligatory stage of preparation for treatment
Urgency of radiotherapy planning
A key challenge in radiotherapy is to provide the maximum damaging effect on the tumor while minimizing the radiation dose to the surrounding healthy tissues. Therefore, dosimetric planning of radiation therapy is an obligatory stage of preparation for treatment.
The main tasks of dosimetric planning:
The dosimetric planning is based on the creation of individual optimal exposure model to achieve the desired result. In this case, it is necessary to ensure the uniformity of the tumor irradiation while maintaining an equally small impact on vital organs.
Planning begins with the creation of a three-dimensional model of the patient based on a series of images made on a specialized computer tomograph. To perform the tasks in full, it is often necessary to perform magnetic resonance and positron emission tomography. With the help of special software, a zone affected by cancer cells, as well as nearby healthy organs are outlined. This is necessary to form a correct dose distribution. When contouring the planned irradiation target, the history of the disease and previous procedures are also taken into account.
After contouring, the patient’s virtual model is sent to the specialized dosimetric planning stations, where the parameters are selected and the treatment time is calculated.
The radiation plan is considered ready after reaching the parameters set by the radiotherapist, based on the radiosensitivity of the tumor and the tolerance of healthy organs.
In the pre-radiation preparation of each patient, a number of specialists take part, so this process consists of several stages.
- An X-ray lab technician scans the affected area on a specialized computer tomograph using patient fixation device during treatment, including, if necessary, individual thermoplastic masks.
- A radiographer or a radiologist with the help of special software performs contouring of the organs and structures of interest (tumors, organs located near the irradiation zone, as well as vital organs), and creates a three-dimensional model of the treatment area.
- A medical physicist calculates the radiation treatment plan at the specialized radiation therapy planning stations, based on the doctor’s prescriptions and treatment protocols. Then, taking into account the technical characteristics of the radiotherapy device, special parameters and coefficients, a treatment plan for each patient is created ― in such a way as to protect the healthy structures and to bring a therapeutic dose of radiation into the tumor.
- A radiotherapist participates in every stage of the patient’s preparation. During the scan, the radiotherapist determines the areas of impact, during contouring ― sets the boundaries of the tumor. Also, the radiotherapist gives a prescription for doses and approves a physicist-calculated treatment plan. During the entire course of treatment, the physician observes the patient, makes adjustments to the treatment procedure, and gives recommendations on concomitant therapy, if necessary.
At any stage of treatment, the patient can contact the attending physician for advice.
The radiotherapy center “Saknur” uses the newest TomoTherapyTomoHD tomotherapy device, allowing to visualize the tumor position during treatment. This increases the accuracy of the performed manipulations and provides the maximum damaging effect on the tumor with the reduction of the radiation exposure to the surrounding healthy tissues. When calculating treatment plans for TomoTherapyTomoHD, a modern modulation radiotherapy (IMRT) technique is used to maximally exclude healthy organs from the radiation area, thereby reducing side effects and radiation reactions that affect the patient’s quality of life.
The accuracy of therapy planning and the effectiveness of future treatment is ensured by the fact that our specialists (radiologists, oncologists, medical physicists, radiotherapists, etc.) have many years of professional experience.