Officials with ProCure Treatment Centers and Central DuPage Hospital celebrated the grand opening of the center in suburban Warrenville.
Proton therapy is a lot like traditional radiation, killing cancer by preventing the cells from growing and dividing, but the proton beam is billed as being more precise and able to spare healthy surrounding tissue. It's commonly used to treat prostate, colon, head, neck and brain cancer.
Critics say there is still no strong evidence proton therapy is better or safer than traditional radiation.
Still, there is plenty of demand for the alternative therapy.
The first treatment is expected to take place at the end of this month.