Siteman Cancer Center Adds Second TomoTherapy Hi·Art Treatment System

Leading Institution at Barnes-Jewish Hospital and Washington University School of Medicine Applies Helical TomoTherapy to Advance Women’s Cancer Care

MADISON, Wis. – Jan. 7, 2009 – TomoTherapy Incorporated (NASDAQ: TOMO) announced today that the Siteman Cancer Center at Barnes-Jewish Hospital and Washington University School of Medicine, St. Louis, Mo., has commenced treating patients on its second TomoTherapy® Hi·Art® treatment system. Siteman, a National Cancer Institute (NCI) Comprehensive Cancer Center, installed its first Hi·Art system in early 2006. The installation of a second unit enables more cancer patients to benefit from this revolutionary intensity-modulated radiation therapy (IMRT) solution.

“We knew the benefits of arc-based radiation delivery before installing our first TomoTherapy unit. Upon installation, we gained the ability to deliver IMRT in a continuous helical pattern, and the infrastructure and workflow to apply image guidance to each treatment, for every patient,” said Dan Low, Ph.D., associate professor of radiation oncology, Washington University School of Medicine. “This is something we cannot do on any other system. As we’ve become more accustomed to the benefits of this platform, we saw a need for a second Hi·Art system.”

“As a large clinic with multiple treatment devices, we are able to select the best technology for each patient’s unique needs,” added Imram Zoberi, M.D., assistant professor of radiation oncology at Washington University School of Medicine and medical director of Siteman Cancer Center at Barnes-Jewish West County Hospital in Creve Coeur, Mo. “We use TomoTherapy for a wide variety of cases, and have found it is a particularly suitable solution for advanced breast cancer cases with lymph node involvement. These are difficult cases to treat on conventional machines, because of the need for multiple matching fields. With conventional treatment, substantial amounts of lung, heart (for left-sided cases), and musculoskeletal tissue around the shoulder joint are exposed to significant radiation doses. TomoTherapy allows us to minimize radiation exposure to all of these structures.”

Dr. Zoberi continued: “By using TomoTherapy to treat advanced breast cancer cases, we gain a good advantage in plan conformality, critical structure sparing and homogenous dose to the skin surface. We see that patients are tolerating treatment a lot better than with conventional radiation therapy, due to fewer skin issues. We also believe that breast cancer survivors treated with TomoTherapy are less likely to experience limited range of arm motion, which is a common long-term side effect from other forms of radiation. This is an end point in one of our ongoing clinical trials.”

In addition to breast cancer cases, Siteman Cancer Center staff has applied TomoTherapy technology to advance care when organ sparing and tissue avoidance is critical. This includes cancers of the head and neck, esophagus and cervical region. The center’s pioneering use of helical TomoTherapy for cervical cancer, led by Perry Grigsby, M.D., will be presented at the Society of Gynecological Oncologists’ Annual Meeting on Women’s Cancer, Feb. 5-8, 2009, in San Antonio, Tex. Dr. Grigsby is professor of Radiation Oncology, Nuclear Medicine and Gynecologic Oncology Director, Brachytherapy & microRT Treatment Center, Mallinckrodt Institute of Radiology, Washington University.

About TomoTherapy Incorporated

TomoTherapy Incorporated develops, markets and sells advanced radiation therapy solutions that can be used to treat a wide variety of cancers, from the most common to the most complex. The ring gantry-based TomoTherapy® platform combines integrated CT imaging with conformal radiation therapy to deliver sophisticated radiation treatments with speed and precision while reducing radiation exposure to surrounding healthy tissue. TomoTherapy’s suite of solutions include its flagship Hi·Art® treatment system, which has been used to deliver more than three million CT-guided, helical intensity-modulated radiation therapy (IMRT) treatment fractions; the TomoHD treatment system, designed to enable cancer centers to treat a broader patient population with a single device; and the TomoMobile relocatable radiation therapy solution, designed to improve access and availability of state-of-the-art cancer care. TomoTherapy’s stock is traded on the NASDAQ Global Select Market under the symbol TOMO. To learn more about TomoTherapy, please visit TomoTherapy.com.

7 Jan 2009

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