Researchers claim new treatment can detect malignant melanomas without removing tissue

WHEN A doctor suspects a malignant melanoma, the most serious form of skin cancer that kills more than 100 Irish people annually, the scalpel is never far behind. An often painful biopsy is necessary to carry out tests that allow a final diagnosis – more than 600 take place annually in Ireland.

Now a Berlin research company has developed a non-invasive alternative: a laser which it says can detect black skin cancer, or malignant melanotic melanoma, before any skin is removed.

After a successful experimental trial, the clinical trial with the Limes 16-P laser begins this month in the western city of Bochum.

“If it works as we imagine, it will revolutionise the diagnosis of skin cancer because it diagnoses at a molecular level,” says Dr Reinhold Eichhorn, a dermatologist who has conducted successful tests of the laser in Berlin.

“With the laser, one can say before doing anything else what we’re dealing with.”

The laser has been developed by Lasertechnik Berlin, a leading manufacturer of short impulse lasers founded in 1990 as an offshoot of East Germany’s defunct Academy of Sciences.

Three years ago, an LTB research team decided to develop a laser that could detect changes in the pigment melanin. As well as determining skin colour, melanin plays a key role in the degeneration of tissue that culminates in malignant melanoma.

As melanin is fluorescent, the LTB researchers hoped the right kind of laser could detect abnormalities by causing suspect tissue to “glow” differently to healthy tissues.

The biggest blockade along the way – the natural fluorescence of other skin components – was overcome by lengthening the laser’s pulse.

Now, doctors using the laser device can read the “spectral shape” of the tissue under examination and determine if the sample is benign or malignant.

During the experimental test, the laser diagnoses of some 200 samples were compared with the biopsy results of the same tissue.

Samples the laser determined were benign were found later to be harmless; the few malignant samples were flagged by the laser and again later in normal tests.

If that success rate is repeated at a larger clinical trial at the Ruhr University Clinic in this month, Berlin’s LTB hopes to find an industry partner to manufacture and market the device.

“Dermatologist practices are under siege from people with all sorts of machines, so the market isn’t exactly empty,” admits Dr Dieter Leupold, an LTB senior scientist. “But our method is different to others on the market and we are cautiously optimistic.”

There are several benefits of the LTB treatment: though melanoma has a high fatality rate, about 90 per cent of biopsies of moles and other growths removed by dermatologists prove to be benign.

By testing patients in situ, the dermatologists can obviate the need to remove any healthy tissue.

There is hope, too, the laser will be of particular use to opthamologists to detect eye cancer.

Patients interested in participating in the Bochum trial should contact Dr Klaus Hoffmann at the Dermatological Clinic of Ruhr University, Bochum. e-mail: k.hoffmann@derma.de