IMMUNOHISTOCHEMICAL TECHNIQUES IN MOHS MICROGRAPHIC SURGERY - THEIR POTENTIAL USE IN THE DETECTION OF NEOPLASTIC-CELLS MASKED BY INFLAMMATION

Background: Histopathologic evaluation of tissue obtained from Mohs mi crographic surgery is the key step in obtaining complete tumor removal . Residual undetected tumor may result in recurrence. Objective: In ci rcumstances in which the histopathologic interpretation is difficult, we assessed the potential use of immunohistochemical techniques to det ect tumor in Mohs micrographic surgical specimens. Methods: A rapid im munoperoxidase technique with monoclonal anticytokeratin antibodies wa s performed on Mohs frozen sections. Cases selected included morpheafo rm basal cell carcinomas, perineural tumors, and sections with dense i nflammation without apparent tumor. Results: Four cases are described as examples that highlight the potential usefulness of immunostaining of Mohs tissue sections. Anticytokeratin antibodies helped to confirm free tumor margins, thus avoiding the unnecessary sacrifice of normal tissue, and to delineate tumor not identified in hematoxylin and eosin frozen sections. Conclusion: Immunohistochemical staining of Mohs mic rographic surgical specimens with anticytokeratin antibodies is partic ularly useful when dense inflammatory infiltrate is present, because t he latter may obscure any residual tumor. Application of this techniqu e to difficult cases may prevent tumor recurrences or unnecessary exci sion of normal tissue.