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Newest form of proton therapy offered at Siteman Cancer Center

Pencil-beam scanning delivers extremely precise treatments to tumors in sensitive areas

by James GoodwinJuly 8, 2020

Huy Mach

Editor’s note: Video footage available.

A second proton therapy system has been installed at Siteman Cancer Center at Barnes-Jewish Hospital and Washington University School of Medicine and is now available to treat patients. The pencil-beam scanning technology – the most advanced form of radiation therapy available – delivers extremely precise treatments of proton therapy, a type of radiation therapy used to treat cancers of the head, chest, spine and other particularly sensitive areas, as well as pediatric cancers.

Installation of the pencil-beam scanning technology began on the Washington University Medical Campus in early 2019 and was completed in June. Washington University physicians at Siteman have begun treating patients with the technology, including pediatric patients seen through Siteman Kids at St. Louis Children’s Hospital. The therapy also is available to patients who come to Siteman’s main location in St. Louis for treatment from any of Siteman’s five satellite locations in Missouri and southern Illinois.

Both proton therapy systems are housed in the S. Lee Kling Proton Therapy Center on the Medical Campus and are the only two proton therapy units within a 240 mile radius of St. Louis. They are among an array of radiation therapy options available at Siteman.

“As a national and global leader in cancer treatment, Siteman Cancer Center is committed to developing the most personalized treatment plan possible for each patient,” said Stephanie M. Perkins, MD, director of the Proton Therapy Center and an associate professor of radiation oncology at Washington University. “Pencil-beam scanning helps us provide patient-specific care for adults and children, particularly those who have especially complicated cases.”

Proton therapy is a precise form of radiation that targets tumors while sparing surrounding healthy tissues, making it ideal for treating pediatric cancer patients, as well as adults with tumors near sensitive locations, such as the heart, brain, spinal cord or pelvis.

Pencil-beam scanning delivers proton therapy in a single, narrow proton beam aimed directly at the tumor and adjusted for intensity. The beam then “paints” the radiation dose onto the tumor. Alternatively, Siteman’s first proton therapy system, available since 2013, precisely targets the tumor using filters that spread the proton beam across the tumor. That technology remains available for many patients who are candidates for proton therapy. Both systems allow for extremely precise adjustments to the radiation beam, so physicians can precisely target tumors while minimizing damage to surrounding tissue.

Barnes-Jewish Hospital, a member of BJC HealthCare, partners with the School of Medicine to deliver care through the Kling Center. The treatment center is named after the late S. Lee Kling, a visionary St. Louisan who traveled years ago to the East Coast to receive proton therapy for an eye tumor. Kling, a former chairman of The Foundation for Barnes-Jewish Hospital’s board of directors, believed the therapy should be more accessible and available to patients in St. Louis.

“The expansion of proton therapy is an investment in the health of our patients,” said Bob Cannon, president of Barnes-Jewish Hospital and group president of BJC HealthCare. “Siteman continues to be on the forefront of cancer research and treatment, and we are proud to deliver the highest level of care to patients and families from throughout the Midwest and across the country.”

About one in five patients treated at the Proton Therapy Center is a child or teen. A full-time child-life specialist works with such patients and their families to help alleviate any fear or anxiety. Additionally, pediatric patients may watch movies during treatment, which has helped reduce the need for sedation.

For cancer patients overall, radiation therapy is a common treatment. About seven in 10 receive it either in combination with surgery or chemotherapy or another therapy, or as a stand-alone treatment, said Jeff M. Michalski, MD, vice chair of the Department of Radiation Oncology and the Carlos A. Perez Distinguished Professor of Radiation Oncology at the School of Medicine.

“As the technology improves, we want to ensure that our patients have access to the very best care and the latest treatments,” he said. “Pencil-beam scanning complements the array of radiation therapy technologies we offer and is delivered with the expertise of a team of Washington University physicians, physicists and other health-care providers who specialize solely in radiation therapy.”

Both proton therapy units at Siteman are manufactured by Mevion Medical Systems. Other specialized radiation therapy technologies available at Siteman include MRI-guided radiation therapy, CT-guided radiation therapy, Gamma Knife radiosurgery and stereotactic body radiation therapy. All are forms of external beam radiation therapy because the treatments are administered from outside the body. Another type of radiation therapy, brachytherapy, involves implanting “seeds” of radioactive materials next to the tumor. The type of radiation therapy used in a patient’s treatment depends on where cancer cells are located. Washington University radiation oncologists at Siteman select the most appropriate technology based upon the characteristics and location of a patient’s tumor.

Washington University School of Medicine’s 1,500 faculty physicians also are the medical staff of Barnes-Jewish and St. Louis Children’s hospitals. The School of Medicine is a leader in medical research, teaching and patient care, ranking among the top 10 medical schools in the nation by U.S. News & World Report. Through its affiliations with Barnes-Jewish and St. Louis Children’s hospitals, the School of Medicine is linked to BJC HealthCare.

Siteman Cancer Center, ranked among the top cancer treatment centers by U.S. News & World Report, also is one of only a few cancer centers to receive the highest rating of the National Cancer Institute (NCI) – “exceptional.” Comprising the cancer research, prevention and treatment programs of Barnes-Jewish Hospital and Washington University School of Medicine in St. Louis, Siteman treats adults at six locations and partners with St. Louis Children’s Hospital in the treatment of pediatric patients. Siteman is Missouri’s only NCI-designated Comprehensive Cancer Center and the state’s only member of the National Comprehensive Cancer Network. Through the Siteman Cancer Network, Siteman Cancer Center works with regional medical centers to improve the health and well-being of people and communities by expanding access to cancer prevention and control strategies, clinical studies and genomic and genetic testing, all aimed at reducing the burden of cancer.

Jim is associate director of strategic communication at Siteman Cancer Center at Barnes-Jewish Hospital and Washington University School of Medicine in St. Louis. He develops and executes external and internal communications strategies to build awareness of cancer treatment, research, prevention, education and community outreach. He has a bachelor's degree in journalism and a master of science degree in data marketing communications.