21St Century Oncology Holdings, Inc. (RTSX) SEC Filing 10-Q Quarterly report for the period ending Thursday, June 30, 2016

Exhibit 99.1

21ST CENTURY ONCOLOGY HOLDINGS, INC.

21ST CENTURY ONCOLOGY HOLDINGS INC. REPORTS FIRST AND SECOND QUARTER 2016 FINANCIAL RESULTS

FORT MYERS, FL, September 20, 2016 — 21

First Quarter 2016

Total revenues for the first quarter of 2016 were $270.3 million, a decline of 1.9% as compared to total revenues of $275.6 million for the same period in the prior year. Net patient service revenue in our ICC line of business declined $2.9 million, or 3.2%, as compared to the same period in the prior year predominantly due to the conversion of our Jacksonville medical oncology group to a professional services agreement (PSA) with the University of Florida, whereby the Company will invoice for chemotherapy administration only, eliminating the drug portion. In addition, our international net patient service revenue declined $3.3 million, or 12.3%, as compared to the same period in the prior year due to the devaluation in the Argentine Peso. Constant currency international revenue growth was approximately 33.3%, or $7.2 million, quarter over quarter.

Net income for the first quarter of 2016 was $2.6 million as compared to a net loss of $14.4 million for the same period in the prior year. The improvement in net income resulted primarily from a $12.6 million gain on the contribution of a radiation facility to a health system joint venture and changes in fair value measurements of $4.7 million.

Adjusted EBITDA in the first quarter of 2016 was $39.0 million, or 14.4% of total revenues, as compared to $42.3 million, or 15.3% of total revenues, in the first quarter of 2015. The contributors to the adjusted EBITDA decline were a $5.3 million reduction in revenue offset by a $6.3 million decrease in salaries and benefits. In addition, a net increase in medical supply expense of $1.2 million occurred in the first quarter of 2016 as compared to the first quarter of 2015.  This increase was the result of the expansion of medical oncology in SFRO locations, offset to some degree by a reduction in medical supply cost as a result of converting the

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