When hair is exposed to X-rays, the radiation is diffracted in a distinctive pattern by the alpha-keratin that forms hair, the researchers explain in the International Journal of Cancer. Dr Gary L. Corino and Dr Peter W. French, based at Fermiscan Ltd in Sydney, used the technique to look at samples of hair from 13 patients diagnosed with breast cancer and 20 healthy subjects.
Hair was cut as close to the skin as possible to obtain samples of the most recent hair growth. The investigators "successfully and consistently generated the basic alpha-keratin X-ray diffraction pattern in every hair sample."
Ring on hair shows cancer
Hair from the breast cancer patients produced the same features "with the only difference being the superimposition of a new feature." This was a distinctive low-intensity ring.
This ring sign was fairly accurate in identifying breast cancer. It missed one of the breast cancer patients, and showed up as a false-positive in three of the healthy subjects.
The researchers went on to study a length of hair representing 6 months' growth from a breast cancer patient whose hair fell out following chemotherapy. X-ray diffraction at three points along the hair showed clear evidence of the ring at the position furthest from the hair root, a fainter ring at the middle point, and complete absence of the ring close to the root.
"This progressive reduction in the intensity of the ring appears to correlate with the patient's course of treatment and possibly indicates the eradication of the cancer as a result of that treatment," Corino and French suggest.
As for the reason for the ring pattern, they suggest it may represent "incorporation of extraneous lipid material into the fibre as a result of the presence of a tumour." It may also be that the disease affects hair follicles in some way.
Further testing is needed to establish the accuracy of this methodology as a diagnostic test for breast cancer, they conclude. - (Reuters Health)
SOURCE: International Journal of Cancer, February 15, 2008.