Darlene VandenBerg of Pella, Iowa, spent most of last winter in a hospital trying to rid her body of cancer. She fought through 39 radiation treatments, hoping that the grueling regimen would cure the disease located behind her nose and on the left side of her neck.

VandenBerg thought she had beaten her illness, but in August the cancer returned. The news was even harder to take because doctors also told her that her body could not withstand any additional conventional radiation treatments.

But VandenBerg was not about to give up and die. Instead, she contacted University of Iowa Health Care radiologist Ken Zhen, MD. Zhen is a staff member in the University of Iowa Cancer Center's Radiation Oncology Clinic.

After reviewing her prognosis, Zhen decided VandenBerg qualified as a candidate for Intensity Modulated Radiation Therapy (IMRT) using the hospital's new PEACOCK^TM System, a state-of-the-art IMRT planning and delivery system.

The UI Hospitals and Clinics in the only hospital in Iowa and one of only a few in the Midwest to have the PEACOCK^TM System, which is designed to help patients who have exhausted the conventional radiation treatment strategy.

"This was about my only hope," VandenBerg said.

The PEACOCK^TM System allows physicians to target radiation specifically to a tumor's contour and volume no matter the tumor's shape or location. This features make it possible to attack the cancer without damaging nearby, healthy tissue and organs the way conventional radiation therapy does.

"For people such as Darlene, there is no other alternative," Zhen said. "This technological breakthrough in radiation therapy offers renewed hope for these individuals. We can now treat patients to whom we couldn't previously give optimal therapy."

The PEACOCK^TM System treatment uses a powerful, advanced computer program to plan a precise radiation dose. Physicians determine the desired result-maximizing radiation to the tumor with minimum exposure to nearby, normal structures-and PEACOCK's sophisticated CT-scanner and computerized modeling system determine the best way to achieve that result. The system then delivers the radiation automatically.

Using conventional radiation, physicians must first plan the dose and then attempt to fit the tumor to the radiation.

During the treatment itself, the PEACOCK^TM System uses pencil-thin beams of varied intensity. By cross firing the beams, a relatively uniform, lethal radiation dose is delivered to the tumor while protecting surrounding healthy tissue. Because conventional radiation therapy involves radiation beams of uniform intensity, it is difficult, if not impossible to limit the radiation to only the tumor. As a result, doctors must either stop short of optimally treating the tumor or run the risk of damaging nearby structures, which in some head and neck cases can lead to blindness or hearing loss.

The PEACOCK^TM System can plan for and treat multiple targets with essentially no upper size limitations at the same time. PEACOCK's unique features also mean the system can deliver up to 40 percent more radiation to the tumor than conventional radiation therapy systems while sparing 70 percent more of the surrounding tissues.

Each treatment takes 30 to 45 minutes, and an entire treatment course ranges up to 40 days. Many patients experience few, if any, side effects and can continue with normal daily activities during the treatment.

Currently, Holden Comprehensive Cancer Center physician specialists use the system to treat cancer in the head and neck areas. Eventually, UI radiation oncologists plan to use the system to treat cancer in other areas such as well.

"Dr. Zhen has an awful lot of faith in the system," VandenBerg said. "I was impressed that he had so much faith. And because of his faith, I have a lot of faith in him."

For more information about University of Iowa Health Care's PEACOCK^TM cancer treatment system, call the UI Health Care toll-free number, 1-800-777-8442, and ask for the Department of Radiation Oncology.

Radiation oncologist Ken Zhen, MD, evaluates Darlene VandenBerg during a radiation therapy session using the highly advanced Peacock System^TM.

Computer generated image shows radiation therapy plan for Darlene VandenBerg. Note that the tumor in her nasopharnyx and large neck lymph node (red shaded area) are completely covered by high-dose radiation while sparing the spinal cord. This cannot be accomplished by any conventional radiation therapy planning and delivery system.