21St Century Oncology Holdings, Inc. (RTSX) SEC Filing 10-K Annual report for the fiscal year ending Tuesday, December 31, 2013

Exhibit 99.1

21ST CENTURY ONCOLOGY HOLDINGS, INC.

21ST CENTURY ONCOLOGY REPORTS FOURTH QUARTER AND FULL YEAR 2013 FINANCIAL RESULTS

Fourth Quarter 2013 Highlights:

·                  Total company pro forma revenues of $209.2 million, up 23.9% year-over-year, including $5.8 million in pro forma contribution from acquisitions; excluding acquisitions, revenues grew 20.5% year-over-year

·                  Total domestic Radiation Oncology cases completed increased 12.3%

·                  Domestic same market treatments per day increased 7.9%

·                  International cases increased 7.0%

·                  Pro Forma Adjusted EBITDA of $27.2 million

·                  Completed acquisition of OnCure Holdings, Inc. (“Oncure”) on October 25, adding significant scale and opportunity for long term revenue growth and operating synergies

·                  Transitioned corporate identity to 21st Century Oncology brand, recognized globally for high quality integrated cancer care (“ICC”) services

·                  Acquired strategically located radiation therapy facility with certificate of need (“CON”) in Roanoke Rapids, NC; upgrading with advanced technologies and clinical pathways

·                  Entered strategic partnership with ProHealth Care Associates, LLP, the largest physician group practice in the metropolitan New York area, to operate an ICC  practice in Riverhead, NY as well as jointly pursue additional strategic opportunities

Full Year 2013 Highlights:

·                  Total company pro forma revenues of $845.3 million, up 20.7% year-over-year, including $108.8 million in pro forma contribution from acquisitions; excluding acquisitions, revenues grew 6.1% year-over-year

·                  Total domestic Radiation Oncology cases completed increased 13.1%

·                  Domestic same market treatments per day increased 4.3%

·                  International cases increased 5.7%

·                  Pro Forma Adjusted EBITDA of $118.6 million

FORT MYERS, FL, February, 19, 2014 — 21