System Promises More Precise Treatment For Hard-to-Reach Cancers
Radiation oncologists at Thomas Jefferson University Hospital are using an innovative radiation therapy technique to more precisely treat hard-to-reach cancers of the head and neck, spine and several other locations. The promise of the technology, called Intensity Modulated Radiation Therapy, and its delivery system, dubbed Peacock, lies in its ability to develop computerized treatment plans to focus radiation only on the tumor, sparing healthy tissue.
A major limitation of using radiation to treat cancer is the damage it inflicts on normal tissue. Because of this, treatments are limited in intensity, scope and duration.
The system uses layered therapy, explains Maria Werner-Wasik, MD, Assistant Professor of Radiation Oncology at Jefferson Medical College. It allows specific areas of the patient to be treated. A special crane moves the treatment table and the patient during therapy.
Jefferson is the first medical center in the Delaware Valley and one of approximately 26 centers nationwide to have such technology.
Dr. Werner-Wasik explains that in traditional treatments, radiation does not reach tumors uniformly. For many tumors, healthy tissue simply gets in the way. For others, portions of the tumor may vary in thickness and size. Modifying the way radiation is delivered should enable us to get radiation to hard-to-reach margins and also to uniformly irradiate tumors that differ in thickness, she says. It [Peacock] has an ability to conform a high-dose area of radiation to the shape of the tumor, even an irregular shape. Its the radiation oncologists dream to be able to do this.
Peacock allows us to start with what we think is the ideal deposition of radiation for the patients tumor, says Walter Curran Jr., MD, Professor and Chair of Radiation Oncology at Jefferson Medical College and Clinical Director of Jeffersons Kimmel Cancer Center. He calls Peacock conceptually revolutionary.
Radiation cannot easily control some tumors such as those of the lung and prostate. The prostate, for example, is located deeply in the pelvis and is surrounded by normal structures, including the bladder and rectum. If we can increase the radiation dose to prostate or lung cancer tumors, and not to the nearby normal tissue, hopefully we increase the likelihood of cure.
Dr. Werner-Wasik believes that the device will enable radiation oncologists to provide more second courses of radiotherapy It is dangerous in certain situations to give second courses of treatments to some patients, she explains. Peacock may allow us in some cases to treat tumors that recur after initial courses of radiation.
Nomos Corporation of Sewickley, Pa., developed the Peacock technology.