What is Robert Wilson’s mistake?

It is generally accepted that Robert Wilson in his article "Radiological Use of Fast Protons" suggested that protons should be used in the therapy of oncological diseases.

In fact, he described the nature of charged particles, however, it is said in conclusion that medically educated people should decide which particles to use.

Robert Wilson: One naturally asks what are the advantages of fast protons over high-energy electrons such as those from a betatron (4). This question can be answered only by medical workers, and the answers will probably be different for different kinds and sizes of tumors. Certainly the differences between fast electrons and protons are onlly quantitative. The specific ionization for protons is much greater, and the concentration of ionization in a given volume is also greater because the straggling and spreading of electrons is worse. On the other hand, electrons of sufficient energy can be produced by more modest equipment.

Unfortunately, medical workers are not strong in nuclear physics that is why a lot of doctors consider proton therapy to be acceptable only in some cases, in the rest of them electron accelerators producing braking gamma irradiation by means of gamma-gun should be used for therapeutic needs.

So, we are correcting Wilson’s historical mistake and claim that according to fundamental laws of nature proton beam therapy always have an advantage before gamma irradiation therapy since it allows irradiating the tumor with higher doses providing less harm to healthy tissue. 

The growing popularity of proton therapy all over means that installations based on electron accelerators must be prohibited to be used since they bring considerable irradiation dose to healthy tissue.