Beyond Your Cancer

Isoray passionately designs and develops innovative and personalized brachytherapy products that effectively treat many forms of cancer. We believe in pioneering solutions for life beyond your cancer.

Patients Treated

Isoray Medical, Inc. is an innovative company that designs and develops state-of-the-art, personalized brachytherapy products that provide a more cost-effective cancer treatment. Isoray employs approximately 40 employees, dedicated to the introduction of a unique isotope for the treatment of both common and also difficult to treat cancers.

Based in Richland, in the shadow of the Hanford Nuclear Reservation, Isoray leveraged the expertise in the region to develop a proprietary process for manufacturing a sought after new medical isotope, Cesium 131 used in brachytherapy treatment of cancer. Brachytherapy is a technique that places radiation sources (“seeds’) as close as possible to the tumor site to destroy cancer cells.

Cesium 131 has unique characteristics that have evolved into an effective treatment for many types of cancer. Specifically, Cesium 131 is able to provide a highly targeted, fast-acting radiation treatment that is able to deliver its energy in a shorter time period than conventional external beam radiation therapy or other isotopes currently used in brachytherapy, which is not only more cost-effective but typically results in less treatment side-effects.

The initial application for Cesium 131 is for the treatment of localized prostate cancer. The fast-acting nature of the treatment allows men to quickly recover from short term side-effects from radiation and return to normal urinary, bowel and sexual function faster than with other brachytherapy isotopes. A growing body of literature supports faster recovery when Cesium 131 brachytherapy is utilized.

In addition to serving as a novel, more efficient alternative for prostate brachytherapy treatment, Cesium 131 is showing great promise in other applications that previously had limited treatment alternatives, including recurrent gynecological cancers, brain tumors, sarcomas and other aggressive and recurrent tumors. Leading medical centers, hospitals and clinics across the United States are now offering this breakthrough treatment for cancer patients.

The fast-acting nature of the Cesium 131 isotope is well-suited to provide additional targeted radiation at the time of surgery, allowing for the treatment of residual disease while limiting the dose to surrounding healthy tissues. In many cases, the radiation “boost” can be delivered before conventional external beam radiation could even be started — while still delivering higher therapeutic doses.

In the case of brain cancer treatment, Isoray has submitted a 510(k) application for a novel delivery system developed in conjunction with the Barrow Neurological Institute (Phoenix, AZ) and is also pursuing a unique code to provide reimbursement.

Another exciting new application is for the treatment of recurrent gynecological tumors. Physicians at the University of Kentucky are using Cesium 131 to treat women with a less invasive approach, which historically has required extensive, debilitating surgical procedures. Early results are promising.

Isoray Medical is the sole producer of Cesium-131 brachytherapy sources, which are expanding brachytherapy treatments for difficult to treat cancers. Isoray is dedicated to pioneering cost-effective solutions for life beyond a patient’s cancer.


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How is brachytherapy “new again,” 30 years on into Dr. John Sylvester’s career?

Radiation Oncologist Dr. John Sylvester, MD shared a few minutes with us at ABS 2018 discussing recent advancements in prostate brachytherapy and their implications for prostate cancer patients.

Dr. John Sylvester: “Newer does not necessarily mean better.”

Dr. Sylvester discusses how the development of new technology can bring new treatment modalities that are frequently pressed upon patients in spite of brachytherapy’s efficacy and rapid side effect resolution.

Biological effectiveness dose and convenience: Why Cesium-131 is the LDR brachytherapy isotope of choice for Dr. Bradley Prestidge.

Dr. Bradley Prestidge, MD, MS, serves as Regional Medical Director of Radiation Oncology for Bon Secours Medical Group in Norfolk, Va. During the...

Your one-stop shop for the latest in brachytherapy at ASTRO 2018

Capitalizing on the same value ASTRO provides for radiation oncologists to connect with peers in a concentrated way, we invite the entire community to visit the Isoray team at ASTRO 2018.

New long-term data show brachytherapy boost improves freedom from biochemical failure outcomes for T3 high-risk prostate cancer by more than eight percent

In a new study, radiation oncologists find that DR-BT is not only feasible, but also highly effective in men with cT3a and cT3b high-risk prostate cancer.

Join Us at the Following Event


October 21-24, 2018
San Antonio, TX

Booth: 3141

Learn more about Cesium-131 and Blu Build at our cocktail reception.
RSVP at the link below.

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Brachytherapy: An Innovative Disruptor

Dr. Brian Moran, Medical Director for the Chicago Prostate Center, discusses the value of low-dose rate brachytherapy and its disruptive innovation in the cancer treatment field at ABS 2018.