Due to its precision and limited side effects, the particle therapy of cancer is gaining popularity. The number of patients treated with protons and light ions reached 150,000 worldwide. There are currently more than 80 facilities, which often this treatment and several dozen of new ones are in construction. Mostly they are cyclotron-based facilities, which provide proton beams, and only several are synchrotron-based facilities that provide both: proton and carbon-ion beams. The advantage of carbon ions is their higher efficiency in destroying the cancer cells, more localized shape of the Bragg peak and smaller beam scattering in the body. Several of the large centers, which can provide carbon, have experimented with other ions including helium. The advantage of helium over protons is significantly larger precision of the treatment due to lower scattering of alpha particles in the body, especially important for pediatric patients. A facility with therapeutic beams limited to helium, would be smaller and cheaper than carbon-based facility. Here we discuss this option.