[After a slow start, inflow of patients to Dutch proton center patients now as expected]

Hordijk has tried to describe the process about how the proton centers (PTC) came about, and to what extent the expectations regarding the numbers of patients have come true. In his article, the author states that there is a huge overcapacity for proton therapy. In this commentary we substantiate that this statement is incorrect in our opinion. There is no question of overcapacity: the fact that we do not yet treat the licensed patient numbers with proton therapy, 2 to 3 years after the start of proton therapy in the Netherlands, has to do with a calculated build-up (ramp-up) phase. In this commentary we explain why a ramp-up is inevitable with these types of complex innovations, and also why the ramp-up is slightly slower than expected. However, we certainly expect the growth to continue over the next 2 years, so that the patient numbers will be in line with the expected capacity.