CONTACT: JENNIFER CRONIN
2130 Medical Laboratories
Iowa City IA 52242
(319) 335-9917; fax (319) 335-8034
Release: Oct. 6, 1999
UI acquires state-of-the-art radiation therapy system
IOWA CITY, Iowa A new University of Iowa Health
Care radiation therapy system means that UI radiation oncologists can now
better treat patients with cancer in the head and neck region and the central
The UI Hospitals and Clinics' Radiation Oncology Division
is the first facility in the state and one of only a few in the Midwest to
acquire the PEACOCK System, a state-of-the-art treatment planning and delivery
system for Intensity Modulated Radiation Therapy (IMRT).
The PEACOCK System allows physicians to improve radiation
targeting of tumors. It can be used for large tumors and those with complex
shapes. The PEACOCK System's improved targeting makes it possible for the
radiation to attack the cancer without damaging nearby healthy tissue and
"This is truly a technological breakthrough in radiation
therapy," said Ken Zhen, M.D., UI assistant professor of radiology. "It's
a totally different concept of treatment planning and delivery of radiotherapy.
With this new technology using 3-dimensional computerized imaging to tailor
the beam to specific tumors, we can treat patients who previously couldn't
receive optimal therapy."
Conventional radiation therapy uses radiation beams
of uniform intensity, which makes it difficult, if not impossible, for physicians
to direct the ideal amount of radiation to the tumor site. As a result, physicians
must either stop short of optimally treating the tumor or run the risk of
damaging nearby structures, which in some cases in the head and neck region
can lead to blindness or even paralysis.
Rather than treating the tumor with a single, large
uniform beam, IMRT uses many pencil-thin beams of varied intensity. This feature
allows the PEACOCK System to deliver more radiation to the tumor than conventional
radiation therapy systems. By cross firing at the tumor with these beams,
a relatively uniform, lethal radiation dose is conformed and delivered to
the tumor while protecting surrounding sensitive normal tissue.
The other significant difference between conventional
therapy and IMRT is the new technique's powerful and advanced computer program
that plans a precise dose of radiation based on the tumor size, shape and
location. With the PEACOCK System, physicians determine the desired result
such as an optimal dose to the tumor with minimum exposure to the normal structures,
then PEACOCK's sophisticated computerized modeling system selects the best
way to achieve that result. Once the computerized information is generated
and transferred into the PEACOCK's treatment control computer, the radiation
is delivered automatically through a sophisticated micro-multileaf collimator
In addition, the PEACOCK System can concurrently treat
multiple tumor targets of all sizes, each with a different dose prescription.
Each patient treatment takes approximately 30 to 45
minutes and an entire course of treatment ranges up to 40 days, depending
upon the tumor and the amount of radiation required. The treatment is comparable
in price to the conventional strategy.
The UI Hospitals and Clinics bought the PEACOCK System
a couple of months ago. So far, four patients have been or are being treated
with this new technology.
"All patients are tolerating the treatment very well
with good initial response," Zhen said.
Right now, the UI Hospitals and Clinics radiation
oncologists are using the PEACOCK System to treat cancer in the head and neck
areas. Eventually, UI radiation oncologists will use the system to treat cancer
in other areas as well. The PEACOCK System can be used for tumors in the brain,
prostate, lung, esophagus, kidney and liver.
University of Iowa Health Care describes the partnership
between the UI College of Medicine and the UI Hospitals and Clinics and the
patient care, medical education and research programs and services they provide.