• 5/3/2005
  • Asbury Park, NJ
  • Kathleen Doheny
  • Asbury Park Press (www.app.com)

The day may come when patients will spit in the doctor’s office, and no one will be offended. That’s because researchers have designed a test based on human saliva that may detect oral, breast and other cancers in their very early stages.

How soon before such tests are reality? “My prediction for oral cancer tests is a year to a year-and-a-half,” said senior investigator Dr. David T. Wong, a professor and associate dean of research at the UCLA School of Dentistry and the Jonsson Comprehensive Cancer Center, in Los Angeles. For breast cancer testing, he said, it will be longer, because that research is not as far along.

A spokesman from the American Cancer Society, who is familiar with the research, said that more study is needed before the tests can be expected to be in widespread use, however.

In the study, genetic “biomarkers” isolated in saliva predicted oral cancer in about nine out of 10 cases. A biomarker, Wong said, is a kind of genetic “fingerprint” for the disease. “These ‘fingerprints’ occur in a totally noninvasive fluid, saliva,” he said.

Wong’s team isolated the genetic material, called messenger RNA, from saliva to evaluate whether it might have diagnostic value for detecting cancer in its earliest stages. The scientists looked for patterns or changes in this mRNA that might predict cancer.

Overall, the researchers collected saliva and blood samples from 32 patients with oral cancer, 40 patients with breast cancer, and from the same number of healthy controls. They then compared samples from each group, looking for telltale patterns or changes in the mRNA.

“In saliva,” said Wong, “there are 3,000 different mRNAs. But only four (patterns) predict oral cancer. We don’t know (yet) how many predict breast cancer.”