Laura Esserman Discusses "Ultralow-Risk" Breast Cancer Study on NPR

Laura Esserman, M.D., MBA, Professor of Surgery and Radiology at UCSF, and Director of the UCSF Carol Franc Buck Breast Care Center, was recently interviewed by NPR about a study she led utilizing MammaPrint, a diagnostic assay (test), which appears to precisely distinguish between "ultralow-risk" breast tumors and more aggressive ones. This test could inform the decision to whether to recommend adjuvant (post-surgical) therapy, potentially sparing patients from the toxic effects of chemotherapy and radiation. 

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 "ultralow-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.

"You can really say to someone, 'You're not going to die of this disease. And we don't have to be aggressive upfront and treat you with everything, just in case,' " says the lead author of the study, breast cancer specialist and surgeon Dr. Laura Esserman, of the University of California, San Francisco. "There are breast cancers that pose little or no systemic risk."

The results build on findings of a 2016 report using the same test that showed 46 percent of women with certain genetic profiles could actually skip chemotherapy with little consequence to their long-term survival.

Esserman says the new study provides the first evidence that it's possible to run a diagnostic test at the time of a breast cancer diagnosis and identify very low-risk tumors. From this study and others, Esserman says, it appears that about 20 to 25 percent of tumors being diagnosed today "may be ultralow-risk" and not require treatment after surgery.

Read full story at NPR News: Tumor Test Helps Identify Which Breast Cancers Don't Require Extra Treatment  (NPR News)

Use of Molecular Tools to Identify Patients With Indolent Breast Cancers With Ultralow Risk Over 2 Decades (JAMA Oncology)