Breast cancer therapies are being tailored today to fit the genetic profile of the patient. This approach, called personalized medicine, can help doctors choose the best treatments for their patients. But a study published today in the journal Cancer found many women aren't getting tested to see if they are candidates for one important medication.
Women with early-stage breast cancer should be tested to see if their tumors express the HER2 protein. Those who test positive are candidates to receive the drug Herceptin, which can dramatically lower the risk of the cancer recurring. But the study by researchers at UC San Francisco - which was an analysis of medical literature - concluded that up to 66% of patients who are eligible for testing had no documentation of having the test in their medical records. Up to 20% of patients receiving the drug were not tested or had no record of testing. The study also found that about 20% of HER2 test results may be incorrect.
"The limited evidence available suggests that there are important variations in testing practices and key gaps in knowledge about" HER2 testing strategies," the authors wrote.
As more gene mutations are identified and more targeted therapies become available, testing strategies should be clarified for doctors and patients, they said.
"Given the rapid growth in this area - for example, there are more than 6,000 articles on gene-disease associations this year and more than 1,300 genetic tests making their way to market - evidence-based information will become a necessity if these new technologies are to be used wisely."
More information on HER2 testing can be found on the American Society of Clinical Oncology's website.
-- Shari Roan
Photo credit: Carlos Chavez / Los Angeles Times