34βE12 is the Most Reliable Marker for Keratin-Derived Cutaneous Amyloid: A Comparative Study

Congo red (CR) remains the most commonly used stain by pathologists to detect amyloid deposition. CR, however, has limitations including variable sensitivity with potential of false negative results. We investigated the staining intensity of CR in comparison to commercially available cytokeratin immunohistochemical markers in a series of primary cutaneous amyloidosis originating from keratin filaments.