Michelle Andrews/Kaiser Health News

The past decade has witnessed a rapid expansion of genetic tests, including new instruments to inform patients who have been diagnosed with breast cancer about the risk of recurrence and to guide their treatment.But the clinical significance of many of the inherited mutations that can now be identified remains unclear, and experts are torn on when and how to deploy all the new tests available. Patients are sometimes left paying out-of-pocket for exams that are not yet the standard of care, and even the most up-to-date oncologists may be uncertain how to incorporate the flood of new information into what used to be standard treatment protocols.