Tests on a new anti-cancer treatment have yielded promising results, Myriad Genetics announced Tuesday.

The treatment showed a remarkably high success rate when used on tissue samples from patients who had succumbed to cancer, according to Bill Hockett, spokesman for the Research Park company.

The patients had already undergone chemotherapy, which proved ineffective. But the experimental treatment killed essentially all the cancer cells in the samples?succeeding where conventional treatments had failed.

The treatment works by targeting cancer cells directly, Hockett said.

Chemotherapy, a conventional treatment, targets cancer by destroying rapidly dividing cells. But because many cells in the body naturally divide rapidly, chemotherapy does collateral damage?resulting in hair loss and other side effects, he said.

The new treatment uses the natural mechanism by which old or diseased cells self-destruct to destroy cancer cells, but leave healthy cells untouched.

Cancer cells grow out of control and circumvent this mechanism, which is known as programmed cell death.

Myriad has been working on this technique for about six months. Research is still in its early stage, Hockett said.

If a drug is developed, it will not reach the market for another six years.

So far, the treatment has done well against prostate and blood cancers and shows good prospects with others, he said.