EXHIBIT 21.1 AMERICAN ONCOLOGY RESOURCES, INC. LIST OF SUBSIDIARIES AOR, Inc. - incorporated in Delaware AORIP, Inc. - incorporated in Delaware RMCC Cancer Center, Inc. - incorporated in Delaware AOR Management Company of Arizona, Inc. - incorporated in Delaware AOR Management Company of Florida, Inc. - incorporated in Delaware AOR Management Company of Indiana, Inc. - incorporated in Delaware AOR Holding Company of Indiana, Inc. - incorporated in Delaware AOR Management Company of Missouri, Inc. - incorporated in Delaware AOR Management Company of North Carolina, Inc. - incorporated in Delaware AOR Management Company of Nevada, Inc. - incorporated in Delaware AOR Management Company of New York, Inc. - incorporated in Delaware AOR Management Company of Oklahoma, Inc. - incorporated in Delaware CCA Subco, Inc. - incorporated in Oklahoma AOR Management Company of Oregon, Inc. - incorporated in Delaware AOR Management Company of Pennsylvania, Inc. - incorporated in Delaware AOR Management Company of South Carolina, Inc. - incorporated in Delaware AOR Management Company of Virginia, Inc. - incorporated in Delaware AOR Management Company of Texas, Inc. - incorporated in Delaware AORT Holding Company, Inc. - incorporated in Delaware AOR Real Estate, Inc. - incorporated in Delaware