Doctors have gotten much better at detecting and treating breast cancer early. Drug and chemotherapy regimens to control tumors have gotten so effective, in fact, that in some cases, surgery is no longer necessary. In up to 30% of cases of early-stage breast cancer treated before surgery, doctors can’t find evidence of cancer cells in postoperative biopsies. The problem, however, is that there is currently no reliable way to tell which cancers have been pushed into remission and which ones have not.
