
Tumor Test Helps Identify Which Breast Cancers Don’t Require Extra Treatment
For years, doctors have focused on detecting breast cancer at the earliest possible moment after a tumor develops so treatment can start right away. But more and more studies are showing many small, early tumors don’t present a danger.
So, when is it safe to remove a tumor but skip additional treatments like tamoxifen, chemotherapy and radiation?
A study published Thursday in JAMA Oncology suggests that it may be possible to distinguish fairly precisely between “ultra low-risk” tumors that are unlikely to cause problems and those that are more aggressive and likely to spread — thus allowing some patients to avoid unnecessary treatments.
Researchers in the U.S. and Sweden used a diagnostic test called MammaPrint to measure a tumor’s genomic “fingerprint” and compared it with survival time after a tumor was removed. They say they were able to pinpoint patients who had a very low risk of death from breast cancer — even up to 20 years after the first diagnosis.
MammaPrint is a genomic test that looks at a set of 70 genes in a tumor, showing how the genes are controlling the production of the proteins that drive a tumor’s growth. A genomic test of the tumor, which measures how genes are functioning, differs from other genetic tests that determine someone’s hereditary risk of cancer.
The tumor test was approved by the Food and Drug Administration in 2007 to predict whether an existing cancer has the ability to spread. It’s priced at $4,200 and is covered by some insurance plans in the U.S.