Santa Clara, California, April 28, 2005 (BUSINESS WIRE)--Intraop Medical Corporation (OTCBB: IOPM), manufacturer of the Mobetron®, announced that according to research presented at a recent international meeting, intraoperative radiation therapy (IORT) increases survival rates in patients with advanced or recurrent rectal cancer. IORT is a specialized treatment in which patients are given a dose of radiation therapy during surgery directly to the tumor site. IORT has proven to be a valuable adjunct therapy for treating many types of solid tumors.

In a presentation at the 4th International Society of IORT (or "ISIORT") meeting held in Miami, Florida March 17-19, 2005, Harm Rutten, Chief of Surgical Oncology and a Mobetron user from Catharina Zeikenhuis in Eindhoven, the Netherlands, reported the results of a study at Eindhoven using IORT for the treatment of advanced and recurrent rectal cancer. Eindhoven has the largest single institutional experience with this disease in the world. The 5-year survival rate in 260 advanced rectal cancer patients was 60% compared with the expected 5-year survival of about 25% with conventional approaches. For 160 recurrent rectal cancer patients, Dr. Rutten reported a 5-year survival rate of 37% compared with the 5-10% survival seen with conventional approaches. In the subgroup in which the surgeon achieved complete removal of the tumor, the 5-year survival rate with IORT for recurrent rectal cancer increased to 54%.

Umberto Veronesi, world-renowned breast surgeon and Director of the European Institute of Oncology in Milan, gave the keynote address, entitled "Evolution of Local Management Therapies for Invasive Breast Cancer." He noted that preliminary data from a randomized controlled trial in progress under the auspices of the European Institute of Oncology suggest that, for suitably selected patients, a single treatment with IORT produces equivalent results as the conventional treatment for early stage breast cancer, while eliminating 5 weeks of post-surgical radiation treatments. Dr. Veronesi cautioned that longer follow-up would be needed to confirm their findings. The European Institute plans a new trial for women who are also candidates for breast conserving therapy but who are at higher risk for recurrence or have more aggressive disease. This protocol, similar to ones presented at the meeting by the Mayo Clinic in Scottsdale Arizona (another Mobetron user) and the University of Salzburg, includes IORT at the time of breast surgery, followed by a shorter course of post-surgical radiation therapy treatments than is given with conventional management.

Other presentations at the meeting reported benefits for IORT treatment in a variety of tumor locations. These included sarcomas, pediatric cancers, recurrent gynecological cancer, pancreatic cancer and gallbladder cancer.

Attendees from 12 countries made over 60 oral and 12 poster presentations at this two-day, bi-annual meeting. Five Mobetron users gave nine of these presentations -- two on breast cancer, two on rectal cancer, one on lung cancer (mesothelioma), one on extremity sarcoma, one on kidney cancer, and two on the general usage of the Mobetron.

The Meeting was supported in part by an unrestricted educational grant from Intraop Medical Corporation.

About Intraop

IntraOp Medical Corporation provides innovative technology solutions for the treatment and eradication of cancer. Founded in 1993, IntraOp is committed to providing the tools doctors need to administer intraoperative radiation therapy safely and effectively - for all cancer patients. The company's flagship product, Mobetron, is the first fully portable, self-shielding intraoperative electron radiation therapy device designed for use in any operating room. Key Mobetron benefits include: increased survival rates, better local tumor control, shorter treatment cycles, and fewer side effects. Leading hospitals, from university research centers to specialized cancer clinics in North America, Europe and Asia, use Mobetron as a vital part of their comprehensive cancer program.

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