Test May Help Guide Treatment of Early Breast Tumors
Added On : 8th December 2011
Genetic Test Predicts Risk of Cancer Coming Back if Radiation Is SkippedA test that categorizes very early breast cancers by their genetic fingerprint can tell a woman the likelihood that cancer may come back if she does not have radiation, researchers say.
More than 45,000 women in the U.S. are diagnosed with this early form of breast cancer, called ductal carcinoma in situ (DCIS), each year. The tumors are confined to the milk ducts, meaning they have not invaded the rest of the breast.
The researchers hope is that the test, which looks at the activity of a dozen genes from such noninvasive breast cancers, will help women with DCIS avoid unnecessary radiation.
"Until now, we havent had a good way to predict which individual [noninvasive] tumors will recur," either as a new DCIS or, worse, as an invasive cancer, says researcher Lawrence Solin, MD, chairman of radiation oncology at Einstein Medical Center in Philadelphia.
Solin presented the findings here at the San Antonio Breast Cancer Symposium. Genomic Health, which makes the test and funded the research, hopes to launch it within a few weeks.
About Half Develop Invasive CancerAbout half of women with DCIS will develop invasive cancer over the next few decades if nothing is done, according to Benjamin D. Smith, MD, of the University of Texas M.D. Anderson Cancer Center in Houston. Smith, who specializes in radiation treatment for women with breast cancer, was not involved with the work.
As a result, these women are usually treated as though they have more advanced cancers -- typically with lumpectomy, followed by radiation of the breast, and sometimes hormonal drugs, he tells WebMD.
Compared with surgery alone, radiation reduces the risk of recurrence by 50% to 60%, Smith says.
But radiation is not without side effects. It can cause skin inflammation and make you tired. And over the long term, it can damage heart and lung tissue.
All this points to a need for a test that can guide a discussion on whether radiation treatment can be safely skipped, Solin tells WebMD.