A study of genes from breast cancer tumors shows that these cancers often vary genetically from patient to patient, US researchers report. Understanding the genetic differences of breast cancer may soon help doctors to make more accurate diagnoses, and may lead to more specific treatments.

``Our main goal was to answer the question: `Are all breast cancers the same biologically?'--meaning, do they have the same cell type, the same properties?'' said Dr. David Botstein of Stanford University School of Medicine in California. Botstein is a co-author of the study, published this week in the journal Nature.

``What we discovered is that they are not all the same--they have different subtypes,'' Botstein told Reuters Health. ``The patterns of gene expression are a reflection of the biology of the cell.''

Taking tumor samples from 42 breast cancer patients, the investigators used microarray technology to study the activity of over 8,000 separate genes. This information will allow researchers to further classify tumors genetically.

``Attention to the thousands of individual genes that define the molecular portraits of each tumor, and learning to interpret their patterns of variation, will undoubtedly lead to a deeper and more complete understanding of breast cancers,'' the authors conclude.

``By examining the relationship between a patient's prognosis and the subtype of breast cancer that they have, we may be able to give better treatment,'' Botstein added.

(From chinadaily.com.cn)