World’s first Cs-131 implant for colorectal cancer performed at Weill Cornell Medical Center

IsoRay, Inc. (AMEX:ISR), announced today that on October 10, 2009, Dr. Bhupesh Parashar, Dr. A Gabriella Wernicke and Dr. KS Clifford Chao from the Department of Radiation Oncology, and Dr. Jeffery Milsom from the Department of Gastrointestinal Surgery, at Weill Cornell Medical Center performed the world’s first Cesium-131(Cs-131) implant for the treatment of colorectal cancer.

“The patient tolerated the procedure well and had no evidence of cancer recurrence or any side effects that can be attributed to the Cesium-131 seed implant at the last follow-up visit.”

This implant was performed on a 38-year-old patient with locally recurrent colon cancer who underwent surgical resection of the tumor as a part of the treatment. The patient has a history of multiple prior surgeries and chemotherapy for colorectal cancer.

Dr. Parashar stated, “The patient tolerated the procedure well and had no evidence of cancer recurrence or any side effects that can be attributed to the Cesium-131 seed implant at the last follow-up visit.”

Cesium-131 was chosen for its short half-life and higher dose rate. In addition, the Cs-131 seed brachytherapy procedure has the advantage of relative safety to the medical staff (because of faster radioactive dose fall-off) if the patient requires additional medical care soon after the implant.

Cesium-131 is now being used successfully to treat lung, head and neck, ocular melanoma, and prostate cancers in other patients. In doing so, Cs-131 is expanding brachytherapy options for patients beyond the prostate to locally recurrent cancers in many areas of the body.

Dwight Babcock, IsoRay's CEO, stated, “In 2009, we made significant advancements in our strategy to provide Cesium-131 brachytherapy treatment to physicians to use in their arsenal of tools for fighting cancers throughout the body. We continue to build on that strategy in early 2010 by opening a lung study and moving forward with our preparations to expand the use of Cs-131 to additional areas in the body. We believe brachytherapy using Cs-131 has a unique and growing application to many areas within the body - not just the prostate.”