Tumor profiling is also expanding treatment options for patients who fail first-line therapy or who have rare or aggressive cancers. In some cases, a patient has a tumor that harbors a driver mutation for which targeted therapy is approved for a different cancer type. These therapies have sometimes proven to be effective when used off-label for these patients. In other cases, tumor profiling has revealed driver mutations for which targeted therapies are in clinical development. These patients may be eligible for clinical trials.  Considering the on-label and off-label use of FDA-approved therapies, as well as clinical trials, treatment options are available for most patients across the major cancer types.