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

The introduction of Cesium-131 represents the culmination of decades of work and millions of dollars of investment. Top medical centers, hospitals and clinics across the United States are now offering this breakthrough treatment for cancer patients.

The word brachytherapy derives from the Greek prefix brachy, meaning “short” or “close,” because the titanium capsules containing the radioisotope are implanted directly into the cancerous prostate gland.

Treatment of cancer using low dose radiation or “seed” brachytherapy was pioneered in the 1960’s as an effective alternative to radical prostatectomy. Pioneers in brachytherapy research initially theorized about the use of Cesium-131 in a titanium capsule, however scientific and economic limitations at the time prevented its development and Iodine-125 emerged as an alternative.

Beginning in 1967, Iodine-125 became the first radioisotope manufactured in a titanium capsule, or seed. While its use continues to this day, many patients and doctors in recent years have chosen Palladium-103, a faster-acting, shorter half-life isotope than Iodine-125. In order to obtain the clinical benefits of Palladium’s short half-life, patients and clinicians were forced to settle for lower energy or tissue penetrating power.

A team of scientists continued to believe the physical characteristics of Cesium-131* could potentially provide superior clinical benefits for seed brachytherapy patients. The team developed the patented process for economically separating and purifying Cesium-131 and in 1998 Isoray was founded to manufacture and commercialize Cesium-131 brachytherapy seeds to treat cancers.


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Bringing Compassion and Hope to Cancer Patients

The following article originally appeared in the Winter/Spring 2017 MicroCap Review Magazine. A small company in Richland, WA is dedicated to making...
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Why we are looking forward to SGO 2017: Breakthroughs in treating gynecologic cancer including Cesium-131 Permanent Interstitial Brachytherapy (PIB)

Isoray is excited to be supporting the upcoming Society of Gynecologic Oncology (SGO) annual meeting, which will be held March 12-15 in National...
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Pioneer in Prostate Cancer Treatment Leads Data-Driven Approach to Conquer Disease

With over 6000 prostate cancer brachytherapy procedures to date and thousands of IMRT patients, Dr. John Sylvester is a leading authority on...
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Cesium-131 Brachytherapy yielding better results and changing the patient experience

Cesium-131 pioneer  Dr. Steven Kurtzman, MD, Director of Prostate Radiation of El Camino Hospital’s Center of Advanced Radiation Therapy, has...
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Discussing Value-Based Curative Surgical Option for Non Small Cell Lung Cancer at STS 2017

The Society of Thoracic Surgeons Annual Meeting is the pinnacle of scientific education and new research results delivery in the global...
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Join Us at the Following Events


The Society of Thoracic Surgeons

2017 STS Annual Meeting
January 21 – January 25, 2017
George R. Brown Convention Center
Houston, TX


American Association of Neurological Surgeons

April 22 – 26, 2017
Los Angeles, CA


American Urologic Association Annual Meeting 2017

May 12- 16, 2017
Boston, MA


American Association of Physicists in Medicine

July 31 – August 3, 2017
Denver, CO


American Society for Therapeutic Radiation Oncology

September 24 – 27, 2017
San Diego Convention Center
San Diego, CA

Recent News

Women’s Cancer and Cesium-131 Treatments

Topic of Two Presentations at the 2016 Annual Meeting of the American Brachytherapy Society and World Congress of Brachytherapy RICHLAND, Wash., July 6, 2016 /PRNewswire/ — IsoRay Inc. (NYSE MKT:ISR), a medical technology company and innovator in seed brachytherapy...

IsoRay Appoints Thomas LaVoy as CEO

Richland, WA January 14, 2016 – IsoRay Inc. (NYSE MKT:ISR), a medical technology company and innovator in seed brachytherapy and medical radioisotope applications for the treatment of prostate, brain, lung, head and neck and gynecological cancers, today announced the...