Cancer Treatment Experts Detail Promising New Radiosurgical Techniques for Lung and Liver Cancer Patients

More than 500 oncology professionals at ESTRO Congress hear of breakthrough treatments using high dose rate capability of Varian's TrueBeam(TM) system

LONDON, May 12, 2011 - European cancer experts have reported on developments of some promising
radiosurgical techniques for treating lung and liver cancer using new linear
accelerator technology from Varian Medical Systems (NYSE: VAR). Among the
achievements outlined at a packed "Emerging Technologies Symposium" at the
annual conference of the European Society for Therapeutic Radiology and
Oncology (ESTRO) in London was the ability to treat metastatic liver cancer,
an often inoperable condition, with high dose rate radiosurgery by using
RapidArc(R) radiotherapy on Varian's TrueBeam(TM) platform.

In front of an audience of more than 500 oncology professionals,
clinicians from leading cancer centers in Italy, Denmark and the Netherlands
gave detailed accounts of pioneering radiotherapy and radiosurgery treatments
at their centers. The program was chaired and moderated by Dr. David Landau,
consultant clinical oncologist at Guy's and St Thomas' NHS Foundation Trust
and honorary senior lecturer at Kings College, London, UK.

Dr. Marta Scorsetti, head of radiation oncology at the Humanitas Clinic
in Milan, described an ongoing study involving 43 patients that is aimed at
assessing the safety and feasibility of using RapidArc to deliver
stereotactic body radiotherapy (SBRT) in the treatment of liver metastases.
Results, after seven months, were a local tumor control rate of nearly 94%.

"There is undoubtedly a great need for improved therapies for liver
cancers that cannot be treated surgically, especially those larger than 5
centimeters," said Dr. Scorsetti. "Advances in tumor imaging, radiation
therapy planning, and motion management have made it possible for high dose
radiation therapy to be used safely for treating liver metastases. SBRT
offers the possibility of a non-invasive treatment, delivered in few
treatment sessions."

Professor Ben Slotman, head of radiation oncology at VU University
Medical Center in Amsterdam, presented data from his hospital's lung cancer
program. Clinicians there have treated more than 800 stage 1 lung tumor
patients in the last eight years. The Center, which receives referrals from
more than 70 Dutch hospitals, treats patients on six Varian linear
accelerators, including two TrueBeam devices and a Novalis Tx(TM) machine.

"We recently published the results of a population based study,
demonstrating that the introduction of stereotactic body radiotherapy (SBRT)
in two Dutch provinces resulted in a sixteen percent increase in the use of
radiotherapy with patients above 75 years of age, and that this resulted in
improved survival,"(1) says Prof. Slotman.

Since 2008, all lung SBRT treatments at VU have been delivered using
Varian's RapidArc technology, many on the TrueBeam system. According to Prof.
Slotman, the main benefit of RapidArc for lung patients is the shorter
treatment time with less risk of motion than with earlier generations of
technology. "This is especially important for SBRT, where high doses are
delivered over fewer treatment sessions," he says. "The delivery of the
highest dose for lung tumors was reduced from 30 minutes to just six minutes.
With the introduction of TrueBeam technology, the integration between imaging
and treatment delivery has been improved. By using the High Intensity Mode in
the very near future, we expect to reduce the treatment time to less than
three minutes."

Professor Cai Grau, head of radiotherapy research at the Department of
Oncology, Aarhus University Hospital in Denmark, outlined his center's work
in dynamic adaptive radiotherapy techniques for head and neck cancer
treatments.

Speed is a critical issue when using images to adapt a treatment over a
multi-week course of radiotherapy. "Re-optimizing the treatment plan based on
daily 3-D images of the patient's anatomy allows us to reduce risks
associated with anatomical changes such as tumor shrinkage over a course of
treatment," said Professor Grau.

Doctors at Aarhus University Hospital treat patients on 10 Varian linear
accelerators, all of them equipped with the On-Board Imager(R) device for
image-guided radiotherapy, and capable of three-dimensional cone-beam CT
imaging. Two TrueBeam systems are currently being installed and are due to
start treating clinically in four months.

TrueBeam

Designed to advance the treatment of lung, breast, prostate, head and
neck, and other types of cancer, Varian's TrueBeam platform for image-guided
radiotherapy and radiosurgery was introduced in April 2010 as the first
fully-integrated system designed from the ground up to treat a moving target
with a high level of speed and accuracy.

Applicable for all forms of advanced external-beam radiotherapy including
image-guided radiotherapy and radiosurgery (IGRT and IGRS),
intensity-modulated radiotherapy (IMRT), stereotactic body radiotherapy
(SBRT) and RapidArc(R) radiotherapy, TrueBeam can deliver treatments with a
dose delivery rate of up to 2400 monitor units per minute, double the maximum
output of conventional systems. This makes it possible to offer shorter
treatment times for patients, and to improve precision by leaving less time
for tumor motion during dose delivery. More than 225 TrueBeam systems have
now been ordered by treatment centers around the world, and more than 65
installations are completed or in process.

RapidArc

RapidArc technology quickly delivers a precise image-guided IMRT
(intensity modulated radiotherapy) treatment two to eight times faster than
conventional IMRT.(2,3) Dose is delivered through a beam-shaping aperture
that is continually reshaped to match the shape of the tumor as the treatment
machine rotates around the patient. Over 1,600 RapidArc systems have been
ordered, with nearly 1,000 of those deployed at treatment centers around the
world.

Editorial contact: Neil Madle, Varian Medical Systems, +44-7786-526068

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, 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 5,500 people who are located at manufacturing
sites in North America, Europe, and China and approximately 70 sales and
support offices around the world. For more information, visit
www.varian.com.

(1) Palma et al., Impact of Introducing Stereotactic Lung Radiotherapy
for Elderly Patients With Stage I Non-Small-Cell Lung Cancer: A
Population-Based Time-Trend Analysis. J Clin Oncol 28, 5153-5159, 2010.

(2) Mayo et al., Initial Experience with Volumetric IMRT (RapidArc) for
Intracranial Stereotactic Radiosurgery. Int J Radiat Oncol Biol Phys 78:5,
1457-1466, Dec 2010.

(3) May Y et al. Hypofractionated stereotactic radiotherapy for brain
metastases: a dosimetric and treatment efficiency comparison between
volumetric modulated arc therapy and intensity modulated radiotherapy.
Technol Cancer Res Treat. 9:5, 499-507, Oct 2010.

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