VILLIGEN, Switzerland, March 22 /PRNewswire-FirstCall/ -- Clinicians at the Paul Scherrer Institute in Switzerland have begun clinical treatments using the world's first commercial superconducting cyclotron for routine medical use, enabling high-precision proton therapy treatments for a range of cancer patients. The new cyclotron from Varian Medical Systems' Accel group is a key component of the equipment and is expected to facilitate more accurate treatments with fewer side effects. Two patients with chordomas - bone tumors in the spinal region - were the first to be treated using protons generated by the new 250 MeV cyclotron, which is designed for high efficiency, low energy consumption, high reliability and modern treatment features such as spot scanning, enabling highly effective proton dose distribution in three dimensions, and beam intensity modulation. Dr. Martin Jermann, head of the PROSCAN proton therapy program at the Paul Scherrer Institute (PSI), said, "The first treatments went smoothly and we intend to increase the number of patients treated per day to ten over the next few weeks. The objective of such proton therapy treatments is to cure the patients and to minimise both short-term and long-term side effects." The Varian/Accel superconducting cyclotron represents a dedicated proton source for the PSI equipment, with beam-lines to supply up to 250 MeV protons to the spot-scanning gantry for deep-seated tumor treatments. PSI operates the world's first and only compact scanning gantry for proton radiation therapy of deep-seated tumors. The spot-scanning technique developed at PSI enables malignant tumours to be targeted with high precision deep inside in the body, and their growth successfully stopped, without damaging healthy tissue around the target area. Protons have excellent physical properties for radiation therapy, which enable clinicians to very precisely control the shape of the dose distribution inside the patient's body. The depth of the proton beam can be precisely controlled, which means healthy tissue behind the tumor can be spared as effectively as adjacent tissue. Dr. Jermann said that the new cyclotron would allow the institute's proton therapy facility to operate all year rather than being limited to just 6-8 months, as was the case with the department's previous equipment. "In addition, the beam characteristics and dynamics will allow the development of advanced scanning features, which should enable us to image and treat moving tumors in the lung and breast with extremely high precision," he said. The Varian/Accel superconducting cyclotron, degrader, beam line and gantries will enable PSI to maintain and enhance its international reputation as a unique high-tech laboratory for advanced proton therapy as well as a leading clinical proton therapy research center. Dr. Jermann added, "In future, 150-250 patients per year will benefit from advances in deep-seated tumor therapy at PSI, in addition to the 200-300 eye cancer patients already being treated, with success rates of more than 98 percent." Lester Boeh, vice president of emerging businesses for Varian, said, "This is a real landmark for our proton therapy business and good news for European cancer patients. Varian/Accel's superconducting cyclotron enables proton therapy to be delivered in the most accurate, effective and efficient manner possible and we are delighted that treatments are underway at PSI." About Varian Medical Systems Varian Medical Systems, Inc., of Palo Alto, California, is the world's leading manufacturer of medical devices and software for treating cancer and other medical conditions with radiotherapy, radiosurgery, proton therapy, and brachytherapy. The company supplies informatics software for managing comprehensive cancer clinics, radiotherapy centers and medical oncology practices. Varian is a premier supplier of tubes and digital detectors for X- ray imaging in medical, scientific, and industrial applications and also supplies X-ray imaging products for cargo screening and industrial inspection. Varian Medical Systems employs approximately 3,900 people who are located at manufacturing sites in North America and Europe and in its 56 sales and support offices around the world. In Europe, the company operates manufacturing and engineering centers in Baden (Switzerland), Crawley (England), Haan (Germany), Helsinki (Finland) and Toulouse (France) and has headquarters for Europe, Middle East, India and Africa (EMEA) based in Zug, Switzerland. For more information, visit http://www.varian.com/. About Paul Scherrer Institute The Paul Scherrer Institute (PSI) is a multi-disciplinary research centre for natural sciences and technology. In national and international collaboration with universities, other research institutes and industry, PSI is active in solid state physics, materials sciences, elementary particle physics, life sciences, nuclear and non-nuclear energy research, and energy- related ecology. It is the largest research institute in Switzerland with about 1,200 members of staff. Forward Looking Statements Statements in this press release regarding future business, events, plans, objectives, expectations, estimates, and other similar matters, including, but not limited to, statements using the terms "can" and "expect," constitute forward-looking statements within the meaning of the Private Securities Litigation Reform Act of 1995. Such forward-looking statements contained in this press release are subject to risks and uncertainties that could cause actual results to differ materially from those anticipated, including, but not limited to, the risks described in the company's Annual Report on Form 10-K and other reports filed from time to time by the Company with the Securities and Exchange Commission. These forward-looking statements represent the Company's judgment as of the date of this press release. The Company assumes no obligation to update or revise these forward-looking statements because of new information, future events, or otherwise. Neil Madle Varian Medical Systems +44 7786 526068, DATASOURCE: Varian Medical Systems CONTACT: Neil Madle of Varian Medical Systems, +44 7786 526068, Web site: http://www.varian.com/

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