Our proton radiotherapy procedures for the treatment of malignant lymphomas in the mediastinum (a central compartment in the thoracic cavity) have been included in the world’s treatment protocols, are adopted by other world proton centres and may reduce the radiation exposure of e.g. the heart and lungs in an absolutely fundamental way, thereby significantly eliminating the risk of developing heart and lung diseases (such as heart attack, heart rhythm disorders, pulmonary fibrosis, etc.). Proton therapy is also able to substantially eliminate exposure of the spinal cord to radiation, thus reducing the risk of it being damaged.
Malignant lymphomas are conditions which very often affect people at a young age. The patients usually recover after cancer treatment; therefore, it is desirable to prevent any side effects of the treatment to the maximum extent. Malignant lymphomas rank among tumours highly sensitive to irradiation. Radiation therapy is usually recommended as an additional treatment after previous systemic therapy (chemotherapy, biological treatment). Irradiation of malignant lymphomas can be challenging because it requires dose reduction to surrounding high-risk organs, which in most cases cannot be reliably achieved with conventional radiotherapy. In the long-term, patients are threatened especially by the development of secondary malignancies and cardiovascular diseases after radiation treatment.
It is essential to always carefully consider the indications for irradiation. The need to include radiotherapy in the treatment scheme is confirmed by clinical studies. In the Czech Republic, we follow the recommendations of the Czech Lymphoma Study Group (CLSG), which reflect the latest results of those clinical studies and are updated regularly. When carrying out radiotherapy, we also follow the recommendations of ILROG (International Lymphoma Radiation Oncology Group). It has been confirmed by 14 studies that proton radiotherapy significantly reduces the radiation burden of high-risk organs and should therefore be considered in patients in whom it is able to significantly reduce doses to high-risk structures.
Because breathing movements can disrupt the correctness and accuracy of proton irradiation, we also use the deep inspiration breath-hold technique for radiotherapy of lung tumours. The Dyn’R device is used for this purpose.
The deep inspiration breath-hold technique is chosen because it is important that the irradiated part of the body (volume) is irradiated each day in the same way. As the irradiated volume moves with the breath, we need to ensure that your body maintains the same position in every procedure. It is best ensured by holding the breath at a certain level. To determine this level, you need to first undergo training of deep inspiration breath hold (Dyn’R training).
Training of deep inspiration breath hold is done in supine position while the patient is connected to the spirometer through an antibacterial filter and mouthpiece. Your nose is pegged so that all the expired air flows through your mouth. You will wear special video glasses to follow the breathing instructions. Our experienced employee will patiently guide you through the entire training process and you will have enough time to try everything out. You don’t have to worry about anything.
For patients with mediastinal involvement, a combination with controlled maximum inspiration (deep inspiration breath hold-DIBH) has been used in PTC since April 2015. This technology is currently the most gentle available technique for irradiation of mediastinal tumours, in some cases, it is further combined with the treatment of movements not related to breathing, e.g. pulsation of large vessels or the heart (rescanning). These options ensure safe irradiation of otherwise problematic areas such as the mediastinum (a central compartment in the thoracic cavity) and the upper abdomen (infrahepatic area). Currently, only a few proton centres in the world offer such a technologically advanced treatment. Thanks to our experience, we are part of the international ILROG team that formulated consensus guidelines for proton RT of mediastinal lymphomas in adults.
Doctors together with the physicists of the Prague Proton Center participate in the creation of domestic and foreign guidelines for the treatment of lymphomas, give lectures at domestic and foreign congresses and participate in clinical studies related to radiotherapy of lymphomas, such as the analysis of dosimetric and radiobiological models comparing modern technologies of photon vs. proton radiotherapy.
