Simple blood test could replace biopsy.

• Position: Cancer Detection

It is possible a simple blood test could be developed to determine whether gene mutations associated with cancer exist without the need of locating and testing tumor tissue, suggest some surprising findings from scientists at the University of Texas MD Anderson Cancer Center, Houston.

This appears possible following the discovery that tiny particles the size of viruses--called "exosomes"--are shed by cancer cells into the blood; they contain the entire genetic blueprint of cancer cells. By decoding this genomic data and looking for deletions and mutations associated with cancer, researchers believe this discovery could be translated into a test that helps physicians detect cancer and treat patients.

"At the present time, there is no single blood test that can screen for all cancer-related DNA defects," says Raghu Kalluri, chairman and professor in the Department of Cancer Biology. "In many cases, current protocols require a tumor sample to determine whether gene mutations and deletions exist and therefore determine whether the tumor itself is cancerous or benign. To procure tumor tissue, one needs to know that a tumor exists and...