December 28, 2012
Expensive Proton Beam Therapy No Better Than Traditional Treatment For Prostate Cancer
Lawrence LeBlond for redOrbit.com - Your Universe Online
A new study published this week in the Journal of the National Cancer Institute has found that an expensive prostate cancer radiation treatment provided no long-term benefit over traditional radiation. The treatment, known as proton beam therapy, uses atomic particles to treat cancer and is said to target tumors more precisely than traditional methods. However the method has been found to produce no fewer side effects than much cheaper traditional radiation therapy, and is also no better effective.
When it comes to side effects, “there's really no difference in outcomes between proton radiation and IMRT for men with prostate cancer,” said lead author Dr. James Yu, a radiation oncologist at Yale University School of Medicine.
While advocates for proton therapy argue that the treatment blasts radiation directly into the tumor therefore avoiding any side effects, researchers found otherwise. The more common "intensity-modulated" radiotherapy (IMRT) exposes some healthy tissue to radiation and has been known to increase the number of side effects. And after one year of research, the study team found the new method also produces the same number of side effects as the traditional IMRT.
The new proton therapy method is not only expensive to the patient (costing Medicare $32,000 per patient compared to $19,000 for the traditional methods), but the cost for building a particle accelerator large enough to handle the task requires a meager $125 million+.
And while researchers do nothing short of proving that proton therapy is neither better nor safer than traditional methods, it isn´t stopping the growth of proton beam centers across the country. Ten centers are now in existence in the US, according to the National Association for Proton Therapy, with eight more centers under development.
Prostate cancer is the most common cancer in men in the US with 242,000 diagnoses per year, and about 28,000 deaths. However, many men do not die from the disease due to its slow growth rate. And many health-policy experts say the condition is over-treated to begin with.
For the study, Yu and his colleagues tracked Medicare claims in 2008 and 2009 for treatment-related complications in nearly 30,000 men with prostate cancer for up to a year. During the course of the study only two percent of the prostate cancer patients underwent proton therapy and the remainder had IMRT.
After six months, about 10 percent of the IMRT-treated patients, and six percent of the proton therapy patients, had side effects including incontinence, burning sensations during urination or difficulty getting an erection. However, the difference disappeared a year after treatment, when an equal number of patients (one in five) suffered side effects regardless of method used.
“The ball is in the court of the proton folks in terms of proving a benefit,” Yu told Reuters Health.
The study had some limitations, Yu acknowledged. It only covered side effects, and did not compare the effectiveness of the treatments, which proton-therapy advocates said was a significant weakness in the study.
“[If Yu is] willing to make recommendation or clinical judgments based on this sort of data, I think he's at risk to doing a disservice to his patients,” said Dr. Andrew Lee, director of the Proton Therapy Center at the University of Texas MD Anderson Cancer Center in Houston. “It's like trying to read a license plate from 30 thousand feet up in the air.”
Lee said the length of Yu´s study (one year) was not enough time to look at the full scope of the side effects from either treatment. He said the study also failed to include side effects that didn´t require a hospital visit, and didn´t offer how long treatments lasted.
Lee acknowledged that proton therapy isn´t for everyone. He said the treatment was best for young healthy patients.
Yu agreed, noting that it would most likely be useful in treating cancer in children in sensitive areas where minimizing the radiation is critical. But Yu doesn´t recommend it for prostate cancer.
“The cancer center next door or the radiation oncologist in the community will likely do just as good a job at treating prostate cancer with IMRT as a proton center three times out of the way,” Yu told Reuters Health.