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SRS: A Brief History of Pioneering Technology

Stereotactic radiosurgery, also known as SRS, is a noninvasive, nonsurgical treatment in which high doses of precisely focused radiation are delivered to destroy a tumor.

SRS does not remove the tumor. Instead, it replaces the surgeon’s scalpel with a high dose of radiation that destroys tumor cells with minimal damage to nearby healthy tissue, attacking the tumor with the intent to cure while sparing the patient from most side effects. This advanced form of radiation therapy is delivered in just 1-to-3 treatments, representing an 80-95% reduction in both treatment sessions and anesthetic events compared to traditional forms of radiation therapy. Additionally, more types of cancer can be treated with SRS, including some forms previously considered “untreatable” based on their sensitive locations within the body.



Stereotactic radiosurgery evolved from pioneering work at the University College of London as far back as 1908, when Sir Victor Horsley, a neurophysiologist and neurosurgeon, and his associate Robert Clarke, a mathematician, developed a tool that used a set of three coordinates to calculate a fixed position inside the brain. This “stereotactic” device was used on pets, enabling scientists and researchers to pinpoint a precise location in a minimally invasive fashion. American neurosurgeons Ernest Spiegel and Henry Wycis applied this technology to the human brain in 1947, which ultimately led to the development of multiple stereotactic devices for neurosurgery during the 1950s. It was Lars Leksell of Sweden, however, who envisioned stereotactic radiosurgery and developed the gamma knife to treat intracranial [inside the brain] lesions without opening the skull. His work stimulated worldwide interest and created the field of stereotactic radiosurgery (SRS).1



Over many decades of research and evolution, radiosurgery has become commercially available worldwide and is an accepted methodology for treating certain cancers. Hundreds of thousands of human patients have been successfully treated with SRS—without the risks of open surgery or the side effects of conventional radiation therapy. In addition, the system is being used in at least 40 active clinical studies to further advance stereotactic radiosurgery’s role in treating cancer.

While SRS is widely accepted and available for treating cancer in people, this advanced technology has not been nearly as accessible to pets with cancer.

Until now.

PetCure Oncology is making this revolutionary treatment available to pets through a national network of SRS centers. By applying the best practices learned in human cancer care, PetCure Oncology is dedicated to helping pets beat cancer and maintain a high quality of life. The first center opened in May 2015 in Phoenix, AZ. There are now four locations open, with many more in various stages of development across the country.

Importantly, at the 2015 American College of Veterinary Radiology (ACVR) Annual Radiation Oncology Scientific Meeting, many scientific sessions and research papers focused on the use of SRS in treating animals with cancer. The message was clear: the focus in radiation therapy is shifting from palliative (traditional radiation therapy) to curative (SRS), marking a turning point in the evolution of veterinary cancer treatment.



As we learned from the human cancer field, inroads into treating cancer are made daily. With pets now able to be treated with SRS, we will continue to refine protocols and improve outcomes with the ultimate goal of curing as many pets as possible. We remain hopeful that substantial progress in veterinary oncology is on the horizon and we intend to help lead the way.

Learn more about PetCure Oncology and SRS treatment for pets with cancer

1 http://www.ncbi.nlm.nih.gov/pubmed/19751866