CyberKnife Prostate Cancer Planning Study Published in Leading Radiation Oncology Journal

Study Supports CyberKnife's Clinical Flexibility, Expanding Physicians Options for the Treatment of Prostate Cancer

SUNNYVALE, Calif., April 8, 2008 /PRNewswire-FirstCall/ -- Accuray Incorporated (Nasdaq: ARAY), a global leader in the field of radiosurgery, announced today that a study published in the April 1 issue of the International Journal of Radiation Oncology*Biology*Physics -- also known as the Red Journal -- demonstrates that the CyberKnife(R) Robotic Radiosurgery System can serve as a non-invasive means for delivering high dose rate (HDR) brachytherapy dosing. The study supports the CyberKnife System's clinical flexibility in treating prostate cancer and expands the non-invasive options available to clinicians and patients.

HDR brachytherapy has been shown to be an extremely effective approach for treating prostate cancer, with substantial clinical evidence supporting its usage. Nevertheless, the required insertion of multiple catheters into the prostate, where they remain for the duration of the procedure (typically 1-3 days), makes it an invasive procedure.

This study demonstrates the CyberKnife System's ability to non-invasively deliver complex HDR-like radiation dose sculpting to the prostate, without the need for hospitalization or anesthesia, maximizing patient comfort and convenience. Early clinical outcomes of the study show a rapid reduction in prostate specific antigen (PSA) levels with minimal short-term side effects.

"HDR brachytherapy is an effective, accepted treatment for prostate cancer, but adoption has been limited because it is a difficult procedure for clinicians to deliver and for patients to undergo," said Donald B. Fuller, M.D., radiation oncologist, CyberKnife Centers of San Diego and Radiation Medical Group, and principal investigator in the study. "Our study concluded that CyberKnife radiosurgery can offer the benefits of HDR brachytherapy non-invasively on an outpatient basis that is both easy to deliver and comfortable for patients."

This study, titled 'Virtual HDR(sm) CyberKnife Radiosurgery for Localized Prostatic Carcinoma: Dosimetry Comparison with HDR Brachytherapy and Preliminary Clinical Observations' supports the CyberKnife System's clinical flexibility and demonstrates its capability to create either a uniform distribution of radiation across the prostate or a pattern of dose that is similar to HDR brachytherapy. The System's ability to track the location of the prostate, detect its position and correct the treatment beam angle continually throughout treatment ensures that either type of plan can be delivered accurately, accounting for the motion of the prostate during the treatment. The CyberKnife System gives clinicians a variety of non-invasive treatment delivery options, allowing them to customize the treatment to each patient's specific case.

"We are pleased to have published support of the CyberKnife System's diverse capabilities in prostate cancer planning and look forward to further clinical evidence following the publication of long term follow-up studies," said Eric P. Lindquist., senior vice president and chief marketing officer of Accuray.

Explanation of HDR Brachytherapy

HDR brachytherapy is a procedure commonly used in the treatment of prostate cancer. The procedure involves the insertion of catheters into the prostate gland, and then the delivery of a series of radiation treatments through these catheters. A computer-controlled machine forces a seed containing a high energy radioactive source into the catheters one at a time, and then controls how long this seed remains in each of the catheters. This method allows different regions of the prostate to receive different doses of radiation (i.e., regions of the prostate expected to have large numbers of tumor cells receive higher doses of radiation than other parts of the prostate that may have a smaller amount of tumor cells).

About the CyberKnife(R) Robotic Radiosurgery System

The CyberKnife Robotic Radiosurgery System is the world's only robotic radiosurgery system designed to treat tumors anywhere in the body non-invasively. Using continual image guidance technology and computer controlled robotic mobility, the CyberKnife System automatically tracks, detects and corrects for tumor and patient movement in real-time throughout the treatment. This enables the CyberKnife System to deliver high-dose radiation with pinpoint precision, which minimizes damage to surrounding healthy tissue and eliminates the need for invasive head or body stabilization frames.

About Accuray

Accuray Incorporated (Nasdaq: ARAY), based in Sunnyvale, Calif., is a global leader in the field of radiosurgery dedicated to providing an improved quality of life and a non-surgical treatment option for those diagnosed with cancer. Accuray develops and markets the CyberKnife Robotic Radiosurgery System, which extends the benefits of radiosurgery to include extracranial tumors, including those in the spine, lung, prostate, liver and pancreas. To date, the CyberKnife System has been used to treat more than 40,000 patients worldwide and currently more than 125 systems have been installed in leading hospitals in the Americas, Europe and Asia. For more information, please visit http://www.accuray.com.

Safe Harbor Statement

The foregoing may contain certain forward-looking statements that involve risks and uncertainties, including uncertainties associated with the medical device industry. Except for the historical information contained herein, the matters set forth in this press release, clinical studies, regulatory review and approval, and commercialization of products are forward-looking statements within the meaning of the "safe harbor" provisions of the Private Securities Litigation Reform Act of 1995. Forward-looking statements speak only as of the date the statements are made and are based on information available at the time those statements are made and/or management's good faith belief as of that time with respect to future events. You should not put undue reliance on any forward-looking statements. Important factors that could cause actual performance and results to differ materially from the forward-looking statements we make include: market acceptance of products; competing products, the combination of our products with complementary technology; and other risks detailed from time to time under the heading "Risk Factors" in our report on Form 10-K for the 2007 fiscal year, as updated from time to time by our quarterly reports on Form 10-Q and our other filings with the Securities and Exchange Commission. The Company's actual results of operations may differ significantly from those contemplated by such forward-looking statements as a result of these and other factors. We assume no obligation to update forward-looking statements to reflect actual performance or results, changes in assumptions or changes in other factors affecting forward-looking information, except to the extent required by applicable securities laws.

SOURCE Accuray Incorporated
04/08/2008
CONTACT: Susan Lehman of Rockpoint Public Relations, +1-510-832-6006,
susan@rockpointpr.com; or Stephanie Tomei, Public Relations Manager of Accuray
Incorporated, +1-408-789-4234, stomei@accuray.com
Web site: http://www.accuray.com