The 'City of Hope' will invest $1 billion in a new hospital and research center on the site of a former air base in Irvine that will enhance the way cancer care is delivered in the region.

The large-scale facility will primarily serve Orange County, where nearly 20% of cancer patients leave the area for advanced care, City of Hope said. Many of them travel as long as two hours to City of Hope’s headquarters in Duarte, a city east of Pasadena.

The 'City of Hope' said last year that it would build a $200-million cancer treatment facility in Great Park Neighborhoods, but the project announced Tuesday reflects an expansion to include a hospital and a research facility conducting clinical trials of new drugs and devices.

The complex on land that was once part of Marine Corps Air Station El Toro will be “way more substantial than we had originally planned,” The 'City of Hope' President Robert Stone said. “The demand from people living in Orange County led us to expand the vision.”