US Oncology Inc. is one of the United States largest networks of community oncologists and cancer researchers with more than 500 affiliated sites of care, including 100 radiation facilities and around 1,400 physicians. As one of the United States' leading integrated oncology companies, it serves more than 850,000 patients in communities throughout the United States. US Oncology Inc. provides oral oncology therapies and care support to patients throughout the 50 states. Additionally, the firm is one of the largest community-based cancer care and research networks in the United States.