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American Brachytherapy Society LDR Prostate Brachytherapy Treatment Consensus Paper Recognizes Isoray’s Cesium-131

Sep 28, 2021

RICHLAND, WASHINGTON – September 28, 2021 – The American Brachytherapy Society (ABS) has recognized Isoray’s Cesium-131 in its recently released new consensus statement on the subject of low dose rate (LDR) prostate brachytherapy. This marks the first time Cesium-131 has been included in ABS’s highly respected consensus guidelines. Because Cesium-131 seeds were not available as a treatment until 2004, long-term outcomes following Cesium-131 prostate brachytherapy seeds have only recently been available.

ABS does not rank or endorse any specific treatment option, but rather is focused on evaluating evidence and providing insight into research surrounding the use of brachytherapy in addressing malignant and benign conditions.

Reacting to the newly published, evidence-based consensus statement, Isoray CEO Lori Woods noted the importance of the milestone. Woods said, “We are honored that this prestigious organization has included Isoray’s Cesium-131 in these consensus guidelines. It is another important step forward as we continue to innovate and build on our position as a leader in prostate brachytherapy.”

Entitled, Low dose rate brachytherapy for primary treatment of localized prostate cancer: A systemic review and executive summary of an evidence-based consensus statement, the findings are a “guideline intended to present evidence-based consensus recommendations for low dose rate (LDR) permanent seed brachytherapy for the treatment of prostate cancer.”  The paper was the result of work by an ABS convened task force. According to the ABS task force, the results of their comprehensive literature study resulted in their stating that LDR prostate brachytherapy monotherapy is an appropriate treatment option for low risk and favorable intermediate risk disease. In combination with external beam radiation, it also found LDR brachytherapy is appropriate for unfavorable intermediate risk and high-risk prostate cancer treatment.

Cesium-131 has the shortest half-life and highest energy level of the radioisotopes that ABS currently recommends for LDR brachytherapy for the treatment of prostate cancer. Cesium-131’s energy is powerful, allowing it to aggressively attack the cancer being treated. Its shorter half-life means the radiation delivers its treatment dose faster, reducing other issues for the patient that can come from prolonged radiation exposure. The rapid resolution of side effects is an important advantage for patients, allowing them to return to their normal lives quickly.

Isoray is a medical technology company and innovator in seed brachytherapy powering expanding treatment options throughout the body. The company is the world’s only producer of Cesium-131 brachytherapy, which treats prostate cancer and expands internal radiation treatment for difficult to treat brain, lung, gynecological, head and neck, pelvic, and colorectal cancers.


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About Isoray

Isoray, Inc. is a medical technology company pioneering advanced treatment applications and devices to deliver targeted internal radiation treatments for cancers throughout the body. Isoray, Inc., through its subsidiary, Isoray Medical, Inc., is the sole producer of Cesium-131 brachytherapy seeds. Learn more about this innovative Richland, Washington company and explore the many benefits and uses of Cesium-131 by visiting Follow us on LinkedIn and Twitter