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New cancer treatment gives quick, precise doses

Each weekday morning, Don Libby, 75, leaves his boat docked on the Oakland shores and drives to Berkeley's Alta Bates Summit Medical Center for a quick shot of radiation."The valet doesn't even park my car anymore," Libby said one recent morning after his daily stop, which lasted about eight minutes. "He just leaves it at the curb. He knows I'm not in there long."

Libby is one of the first in the Bay Area to undergo a new kind of quick but frequent radiation treatment for prostate cancer that is reportedly leaving patients with fewer side effects than they experience with traditional radiation treatments.

Instead of zapping Libby's midsection with a few beams of high-dosage radiation every few days to eradicate his walnut-size tumor, software called RapidArc helps target it and, while spinning 360 degrees around Libby's body, uses several rays to precisely pinpoint the cancerous cells while limiting exposure to the surrounding healthy tissue and organs.

Dr. Patrick Swift, the director of radiation oncology services at the hospital's Comprehensive Cancer Center, said that for years physicians and physicists have been trying to improve the accuracy and dosage amounts of radiation treatment, hoping to limit the side effects of nausea, rectal bleeding and damage to the bladder and rectum experienced by some patients. While other companies make software that can shorten radiation treatment for prostate cancer to just a few days, Palo Alto's Varian Medical Systems, the maker of RapidArc, extends the overall length of treatment - Libby will go every weekday from late January until mid-March - but limits the time spent on the doctor's table from about 40 minutes per session to less than 10.

According to Varian, the treatment costs about $30,000 and is covered by Medicare in California.

Swift added that the time saved with each patient also has the potential to save hospital costs in the long run because he's able to see more patients in a workday, from about 30 patients before to as many as 45.

"We want to get to the point one day where we can treat it (with such precision) in under a week," Swift said. (Swift said he does not receive any compensation from Varian Medical Systems.)

After Libby was diagnosed late last year, the former boat racer said he considered more aggressive dosages that would have treated his cancer within a week or two. But he decided on the smaller, daily dose spread over time to diminish the effect on the quality of his daily life. He said he preferred to view his cancer treatment as a quick daily errand, more like a stop to pick up coffee.

"By 10 a.m., I'm off and doing the things I need to do for the rest of my day," Libby said. "I don't even feel like I'm sick."

That's the point, said Swift. "If we don't have a cure, my second priority as a physician is to minimize the risk of injury during treatment and improve the safety of the radiation delivery. My patients are reporting they're comfortable."

Though RapidArc was cleared for use by the FDA in January 2008, there are no published peer-reviewed clinical studies that measure the outcomes for patients with prostate cancer. But there are studies that show that RapidArc delivers the radiation treatment faster than previous delivery systems. And because patients are on the table for a shorter period, there's less chance that the prostate will move and less chance that the radiation will strike surrounding healthy tissue.

Dr. Jonathan Simons, an oncologist and president of the Prostate Cancer Foundation in Santa Monica, said that although the published data on RapidArc is limited but promising, he viewed the technology as an "incremental improvement" on treating prostate cancer.

Simons added that reduced time in the hospital alone could have a positive emotional impact on patients, but has not yet been studied.

"The more you're reminded you're sick, maybe the more sick you feel," Simons said. "There's an emotional side effect of not being in a hospital all day."

Dr. Kamal Patel, a radiation oncologist at the Cancer Treatment Centers of America in Zion, Ill., said the RapidArc treatment is part of a broader push in radiation treatment called "dose painting" - where highly advanced software allows the beams to precisely target cancer cells, even while accounting for the slightest movement of the prostate (up to 2 millimeters) while the patient is lying on the table.

"We've learned in the last 10, 20 years that we're able to survive cancer," Patel said. "So now the quality of life during and after treatment needs to improve. Reducing the toxicity to the surrounding tissues and organs allows us to do that."

The advances in technology also have implications for treating breast, neck and brain cancers, Swift said. Delicate areas where doctors once resisted aiming radiation for fear of damaging nearby organs are becoming new target zones.

Libby said he was happy to be part of a new treatment, even if it meant rescheduling his daily regimen.

"Considering the alternative, going in every day for a few minutes isn't bad at all."

Facts about prostate cancer

In 2008, 24,380 new cases of prostate cancer were diagnosed in California, according to the National Prostate Cancer Coalition.

-- The disease is the most common cancer among American men.

-- One in 6 American men is at lifetime risk of contracting prostate cancer.

-- An estimated 28,660 American men died from the disease in 2008, up 3 percent from 2007.

-- More than 90 percent of prostate cancer cases are found while the cancer is still either local or regional, and nearly 100 percent of these men are still alive five years after being diagnosed.

-- According to the Mayo Clinic, men can "help avoid prostate cancer by exercising and eating a low-fat diet rich in fruits, vegetables and fish. Maintaining a healthy weight can also help reduce your risk."

-- It is recommended that men older than 50 be screened for prostate cancer every two years, with either a digital rectal examination or an ultrasound. Experts also suggest that men older than 50 get a prostate-specific antigen test every two years. If the results indicate that there might be a problem, doctors may recommend a biopsy, which is considered the definitive test for prostate cancer.