Evaluation of Laboratory-Derived Immunohistochemical Assays for Folate Receptor α Expression in Epithelial Ovarian Cancer and Comparison With a Companion Diagnostic

These data highlight the need for caution in antibody selection when developing immunohistochemistry-based assays, as some antibodies failed to cleanly and specifically identify FRα expression. We identified 2 antibodies appropriate for further investigation; however, as developed, these antibodies may overselect patients for treatment with FRα-targeted therapies.