Photoacustic Cancer Detection

By exposing a patient's blood sample to bursts of laser light, detached melanoma cells can be coaxed into giving off an acoustic (ultrasound) signature, the techique is believed to be very sensitive, measuring levels as low as 10 tumor cells per sample.

Source
Writing in the journal Optics Letters, the University of Missouri team said they combined laser techniques from optics and ultrasound techniques from acoustics, using a laser to make cells vibrate and then picking up the characteristic sound of melanoma cells.

They said they were able to detect melanoma cells obtained from actual patients.

The dark, microscopic granules of melanin in the melanoma cancer cells absorb the energy bursts from the blue-laser light. As the melanoma cells expand and contract, they generate crackling sounds that can be picked them up with special microphones and analyzed by computer.

That's quite a useful diagnostic tool, inexpensive, quick and relatively painless, it's only drawback at this time seems to be a rather limited range, the method is currently only capable of spotting melanoma.



alternative source:

www.eurekalert.org...

The general term for detecting and/or treating cancer with laser based techniques is photodynamic therapy.

NIH & Photodynamic Therapy