Appraisals and pitfalls of myoepithelial cell staining by Levanol Fast Cyanine 5RN

In the search for specific staining of myoepithelial cells in human normal and pathologic mammary tissue we applied the milling dye Levanol (Supranol) Fast Cyanine 5RN. Reports from literature on this staining method were considered, and efforts were made to improve the procedure. Different fixatives were tested, and the pretreatment of the sections was modified. Five nuclear stains were tried but were finally omitted. Counterstain of the connective tissue proved useful. The advantages of the different modifications are discussed.