The HER2 testing conundrum

By Kelley Luckstein

A recent study from the University of California, San Francisco, reveals that one in five HER2 tests gives the wrong answer. Furthermore, the article, which reviews the medical literature, reports that as many as two-thirds of breast cancer patients who should be tested for HER2 are not, and consequently a significant fraction of women treated with Genentech's Herceptin (trastuzumab) have never been tested for HER2 overexpression…

For now, the tests' use may be confined to confirming or clarifying results obtained using other tests. “We need not just technical accuracy but to know if these tests are actually clinically relevant,” says Edith Perez, of the Mayo Clinic Florida in Jacksonville.

Nature, by Malorye Allison, 2/25/2010