Radioterapija s protonskimi žarki
Proton beam therapy

  • Božidar Casar
  • Primož Strojan
Keywords: radiotherapy, protons, Bragg peak, proton therapy, cyclotron

Abstract

Ob kirurškem in sistemskem zdravljenju je radioterapija eden od treh stebrov zdravljenja raka. Izjemen tehnološki razvoj na področju pospeševalnikov nabitih delcev je pripeljal do uveljavitve protonske radioterapije kot terapije izbora pri določenih skupinah bolnikov obolelih za rakom, v prvi vrsti otrok. Velika konkurenčnost med proizvajalci je botrovala postopnemu znižanju cen protonskih pospeševalnikov, ki so v zadnjih letih postali dostopni tudi državam, ki ne sodijo med najbogatejše. Kompleksnost radioterapije s protoni, velikost naprav in še vedno sorazmerno visoka cena so glavne ovire, da protonskih centrov že v tem trenutku ni več in da takšnega centra še vedno ni niti v Sloveniji niti ne drugod v jugovzhodni Evropi. Izbor bolnikov, ki bi imeli pomembno klinično korist od protonske radioterapije, je zahteven in tudi v svetu še ne docela dorečen. Prednost protonske pred konvencionalno fotonsko radioterapijo je v večji biološki učinkovitosti protonskih žarkov. Tudi fizikalno gledano so dozimetrične lastnosti protonskih žarkov bistveno ugodnejše glede sevalne obremenitve zdravih tkiv in rizičnih organov: večina njihove energije se sprosti na mestu, kjer je tumor, za razliko od fotonskih žarkov, kjer se večina energije sprosti v prvih nekaj centimetrih pod površino kože, kjer žarki vstopajo v telo. Podobno kot mnoge druge države je tudi Slovenija pred odločitvijo, kdaj in kako ustvariti pogoje za protonsko terapijo, ki pa jo bo treba sprejeti hitro in transparentno.


Abstract (Eng)

Together with surgery and systemic treatment, radiotherapy constitutes one of the three pillars of cancer treatment. Tremendous technological development of particle accelerators has led to the implementation of proton beam therapy as the treatment of choice for a specific group of patients with cancer, especially children. Competition among several manufacturers has contributed to the lowering of prices of proton accelerator, which have lately also become accessible to less wealthy countries. The complexity of proton therapy, size of accelerators, and lingering high prices are the three main reasons for a relatively low number of proton therapy centres around the world, and the fact that there are no such centres in Slovenia as of yet. While proton therapy is a valid treatment of choice for the particular patient group, it is still difficult to determine unambiguously which patients would benefit from it most. From a strictly physical point of view, the dosimetric properties of proton beams differ significantly from those of photons, and are advantageous compared to photons. Protons traverse the tissue and deposit only a small part of their energy until they reach a certain depth where nearly all of their energy is deposited, while photons deposit their energy almost entirely in the first few centimetres of the tissue exposed to the beams. Like many other countries, Slovenia is at a crossing where it has to decide on the time and mode of photon therapy implementation, which will have to be carried out in a prompt and transparent manner.

Published
2018-07-07
How to Cite
Casar, B., & Strojan, P. (2018). Proton beam therapy. Onkologija : A Medical-Scientific Journal, 22(1), 12-16. Retrieved from https://revijaonkologija.si/Onkologija/article/view/5
Section
Review Article
Page
12-16