Focused Radiation May Control Some Cancers

U.S. medical scientists say they’ve discovered precisely targeted radiation therapy can eradicate all evidence of cancer in some patients.

Researchers from the University of Chicago Medical Center said their ongoing clinical trial found targeted radiation therapy completely controlled all signs of cancer in 21 percent of the trial’s patients who had five or fewer sites of metastatic disease.

“This was proof of principle in patients who had failed the standard therapies and had few, if any, remaining options,” said the study’s senior author, Dr. Ralph Weichselbaum, a professor of radiation and cellular oncology. “We had encouraging results, including several long-term survivors, in patients with stage-IV cancers that had spread to distant sites.”

In 1994, Weichselbaum and colleague Samuel Hellman proposed there was an intermediate state between cancer that had not spread at all and cancer that had spread extensively. They named that state “oligometastases,” meaning cancer that had spread to a few distant sites.

The researchers said the new technique could also be applied after chemotherapy, in cases in which the drugs had eliminated most the smaller cancer, leaving only a few larger tumors behind.

The trial’s latest results are reported in the journal Clinical Cancer Research,