PALO ALTO, Calif., and THE WOODLANDS, Texas, Oct. 26, 2016 /PRNewswire/ -- Varian Medical Systems (NYSE: VAR) and McKesson Specialty Health today announced a strategic agreement for the deployment and servicing of Varian advanced radiotherapy equipment and software over a three-year period across The US Oncology Network and Vantage Oncology affiliated sites of care. This multiyear agreement delivers significant value to oncology providers in The US Oncology Network, which now operates the largest system of radiotherapy facilities in the U.S. following the acquisition of Vantage Oncology earlier this year.