Researchers from The Rockefeller University and Digilab, using a technique called infrared (IR) spectroscopy, have shown that normal-looking cells taken from women with cervical cancer may actually be abnormal. The findings, published in the Dec. 22 issue of the Proceedings of the National Academy of Sciences, may expand the definition of cancer, and lead to improved diagnostic techniques, such as reading of Pap smears.
"These results show that when cervical cancer develops, the normal-looking cells surrounding those that are visibly abnormal have extensive and measurable changes," says co-author Basil Rigas, M.D., an adjunct faculty member at Rockefeller. "Our findings may lead to improved techniques for diagnosing and treating cancer, by shifting the definition of a cancer cell from the current one-which is based on the morphological features of a cell-to one based on chemical changes picked up by infrared spectra."
Doctors usually depend on the Pap test as a method to detect cervical cancer and precancerous lesions known as dysplasia in women. In the Pap test, cells are taken from the cervix and sent to a laboratory, where technicians look at the cells under the microscope. Samples that contain suspicious cells are then evaluated in detail by specialists. The error rate of the Pap test has been reported to be between 10 and 60 percent, in part attributable to its subjective nature.
In the new study, Rigas and his co-author, Menashi A. Cohenford, Ph.D., of the Digilab Division of Bio-Rad, used IR spectroscopy to look at more than 2,000 individual cervical cells from 22 women. Ten of the women were normal, seven had dysplasia and five had cervical cancer. Half the sample was analyzed by IR and the other half by Pap test, confirming the initial diagnosis.
IR spectra reflect the chemical composition of cells. IR spectroscopic analysis
of the so-called normal cells taken from women with dysplasia and cervical
cancer showed that the cells, though normal
Contact: Joseph Bonner