Konwersatorium im. Leopolda Infelda

The basic factor which determines the success of radiotherapy is delivering the highest possible dose of ionizing radiation to the tumor volume while sparing the neighboring critical organs and healthy tissues. Protons with energies from about 60 MeV to 250 MeV are useful for cancer treatment because of the phenomenon of the Bragg peak i.e. increasing of energy deposition the at the end of protons path in tissue and the well-defined range. Therefore, the unwanted doses to healthy organs, particularly the entrance dose, are minimal as compared to MV X-rays used in conventional radiotherapy. This is of particular importance to pediatric patients in whom the probability of later radiation-induced cancer should be minimized.

Ion radiotherapy was proposed in 1946 by Robert Wilson. In 1991 the first hospital – based proton radiotherapy center, with dedicated accelerator, has been put in operation in Loma Linda, California, US. From that time significant progress has been made, particularly due to introducing of the rotating gantry, narrow scanning beams, verification of the dose distribution by PET measurements of induced β + radioactivity and merging the existing diagnostic technologies. Pencil Beam Scanning (PBS) allows to perform Intensity Modulated Proton Radiotherapy, with the best possible dose distribution in the target volume and minimizing doses to critical organs.

In Poland since February 2011 proton patients from Kraków University Hispital suffering from eye melanoma were irradiated at IFJ PAN with 60 MeV proton beam using home-developed AIC-144 cyclotron. In October 2015 Bronowice Cyclotron Centre with the new 230 MeV Proteus C-235 proton cyclotron with the new eye line and two sophisticated proton PBS gantries is fully operational. The eye treatment was moved to the new place. Up to now 36 patients were treated on gantries and 150 patients with eye tumors. The capacity of the center is used only in 20% due to the limited tumor indications in Poland, as regulated by the Ministry of Health. Therefore many Polish patients are still going abroad for the very expensive treatment, which is financed from private sources or by different foundations.