Prostate treatment gets more accurate
Called BAT, the new technology pinpoints the moving target for radiation of cancer.
By Celeste Williams
July 15, 2002
Lewis Snider griped a little about the hardness of the table. But he was willing to endure being prone for the few minutes it would take to shoot six killer beams of radiation into the cancer invading his prostate.
Snider was receiving a well-known method of cancer treatment -- radiation. What he may not have known is that the procedure he was undergoing could revolutionize the treatment of a cancer that kills more than 30,000 men a year in the United States.
Doctors are treating Snider with a new technology called BAT, or B-mode acquisition and targeting. The Central Indiana Cancer Centers and St. Francis Hospital's South Campus in Indianapolis are the only two sites in the state using it.
The problem with treating prostate cancer is that it is literally a moving target. With its tendency to shift position, someone like Snider, who is due to have 25 radiation treatments, could have neighboring, healthy organs radiated and damaged rather than just the diseased tissue. He is about halfway through his treatments.
Standard treatments are based on where the prostate was positioned "on day one, when the patient first came in," said Dr. Morgan Tharp, a physician at the Cancer Centers. In later treatments, "you just assume everything is the same. But in reality, it's not."
BAT uses 3-D ultrasound images to pinpoint the exact location of the prostate each time a patient is treated, allowing doctors to direct radiation to the precise spot.
Both of the cancer facilities started using BAT this summer, said Dan Keeney, spokesman for NOMOS, the Pennsylvania company that builds the systems. Fewer than 20 people have been treated so far in Indianapolis.
So far, Tharp is impressed with the technology. "It's just a simple concept, well-executed," he said.
Peter Garrett, medical director of radiation therapy at St. Francis, said the technology "is going to make a huge difference in the treatment of prostate cancer."
Tharp said traditional imprecise radiation treatments mean "you have not given as much radiation to the prostate as you thought you were, and you are (exposing radiation to) the rectum and bladder."
That can cause residual side effects, he said.
The computers used in the BAT system superimpose the CT scan image (that "day one" picture) on top of an ultrasound image and reveal "where everything is today," Tharp said.
Adjustments are then made to the treatment table to ensure the radiation beams are directed precisely.
"Of course, the net effect is we have given more radiation to the prostate than we used to," Tharp said.
Prostate cancer is the second-leading cancer killer of men in the United States. More than 32,000 men died of the disease in 1998, including 4,400 in Indiana.
The rate of death from prostate cancer in Indiana, 24.1 per 100,000 people, is slightly higher than the national rate of 22.
But of those diagnosed, only 10 percent will die of the disease, medical experts say. Most of the men diagnosed with prostate cancer are 65 years old and older, and are prone to die of other causes -- such as stroke and heart disease.
The medical community has debated ways to best treat prostate cancer after diagnosis. A federally funded study this year said men who are at low risk can take blood tests for prostate cancer less frequently than yearly.
Even Medicare, the government insurance program that covers the elderly, has accepted the BAT technology, paying for treatment and reimbursing "about $75 a day," said Chris Achtein of the Cancer Centers.
Pat Wolfla, who supervises patient care and oncology at St. Francis, said the impact of the new technology may not be known for six months to a year, but "BAT is a very positive step in refinement of the treatment for prostate cancer. We are finding it very exciting."