University alumnus Ralph Roberts and his son, alumnus Brian Roberts, have pledged $15 million towards a $144 million proton-therapy center scheduled to open in 2009.
Other funds will come from the federal government, the Children's Hospital of Pennsylvania and the University of Pennsylvania School of Medicine.
Proton therapy integrates conventional radiation treatment with proton radiation, a technique that targets tumors more accurately and leaves surrounding areas unharmed.
Upon completion, the center will have five treatment rooms and a space dedicated to cancer research. It will also have four gantries - 90-ton machines that deliver therapeutic beams at physician-prescribed locations.
3,000 patients are expected to come to the center - the first of its type in the mid-Atlantic region - each year.
Its proximity to a medical center will facilitate scientific research and improvements to the center, Medical School officials say.
The center will also partner with CHOP to create a pediatric-care facility in the same building.
It will be built on the site of the old Philadelphia Civic Center.
