Toluidine blue stain for mohs micrographic surgery

Since the advent of Mohs surgery and the introduction of frozen sections into the micrographic technique, dermatologic surgeons have experimented with different histopathologic staining methods to highlight neoplastic tissue and ensure clear margins. Currently, hematoxylin and eosin (H&E) represents the most common method for staining frozen sections employed by Mohs surgeons. However, toluidine blue (T-blue) remains a fast and effective stain for Mohs micrographic surgery, especially when treating basal cell carcinoma (BCC).1 T-blue is a basic dye and stains acidic matter.2 The stain is actually a complex of different dyes of slightly different colors.3 During routine histopathology, it is often utilized to highlight amyloid and mast cells in tissue. These appear blue and red-purple in color, respectively.