RapidArc radiotherapy technology delivers highly-precise IMRT treatment

Varian Medical Systems, Inc.Dec 2 2009

Former New Jersey Assemblyman Francis Bodine was surprised and delighted when his radiotherapy treatment sessions for prostate cancer went from about 20 minutes each day to less than five. Midway through his course of treatment, doctors at the Delaware Valley Urology Cancer Center acquired the region's first RapidArc® radiotherapy technology from Varian Medical Systems (NYSE: VAR), making it possible for them to deliver advanced intensity-modulated radiotherapy (IMRT) treatments two to eight times faster than was previously possible

At the time Bodine's treatments began, his doctor was using what was then the state-of-the-art for IMRT--an advanced form of treatment that shapes the beam to match the shape of the tumor and minimizes exposure of surrounding healthy tissues.

"I knew exactly how long my treatments were taking, because I was counting the seconds," Bodine says. "The machine rotated around me and stopped at seven different positions. The time it took to rotate and deliver the radiation from each angle was about 3 minutes and sometimes a few seconds more, so I had to hold still for quite a long time."

When he was switched to RapidArc radiotherapy, the actual treatment time once he was in position, went down to about 80 seconds, Bodine says. "The machine would rotate around my body without stopping at all. It was so quick, it took more time for me to get undressed and go into the room than it did for the actual treatments."

"RapidArc® technology enables us to deliver highly-precise IMRT treatment much faster than was previously possible with earlier technology," says Steven J. DiBiase, MD, chief of radiation oncology services at the Center and clinical associate professor, Robert Wood Johnson School of Medicine. "RapidArc treatments deliver the dose during one continuous arc around the patient. It also uses fewer monitor units--that's a measure of the amount of radiation being emitted--to complete a treatment. That means there is less low-dose spillage being scattered to other parts of the body."

Faster treatments confer another potential benefit for the treatment of prostate cancer. "Speed has the potential to increase accuracy," says Dr. DiBiase. "Prostate tumors can move within the body during longer treatments, due to natural processes like the bladder filling. With RapidArc, the chance of tumor motion during treatment is reduced."

Bodine chose radiotherapy for prostate cancer because he wanted the least invasive treatment option. "I looked at everything--radical surgery, laparoscopic surgery, seed implants, radiation. I talked with about 15 of my friends who had been through this, and everyone had made a different choice. But I decided on this procedure because I felt it was the least invasive. Normally in the winter, we go away, but I said, 'Let's just take care of this.' I concluded my treatments in March, and 3 months later, my PSA had dropped from 3.9 to 0.5. Three months after that, it dropped again, to 0.3."

Bodine reports that he suffered few side effects--an outcome that is consistent with many published studies of IMRT in the treatment of prostate cancer (see select examples below). "I did not have problems with urination, no bleeding or leakage. The only side effect was that I was a little tired in the afternoons during my treatments. This summer, my wife and I traveled to Macinaw Island in Michigan. Now we are making plans for traveling this winter. We'll go to Newport, Rhode Island to see family, and we're still deciding what to see in January, February, March. We're very busy, my wife and I, doing the things we missed out on because of the demands of my career and elected office for so many years. I plan to be around for many years to come."

The American Cancer Society's most recent estimates show that, in 2008 there were 192,280 new cases of prostate cancer in the United States, with over 6,000 of those occurring in the state of New Jersey.