Hematoxylin and Eosin Tissue Stain in Mohs Micrographic Surgery: A Review

BACKGROUND Several factors may affect Mohs micrographic surgery (MMS) tissue section quality. Although other factors may affect section integrity and ease of processing, tissue stains are the cornerstone of histologic diagnosis. When performed incorrectly, visualization and discrimination of microscopic details may be suboptimal and even impossible. Patient harm may result if an accurate diagnosis cannot be made. OBJECTIVE To review hematoxylin and eosin (H&E) technique, the most commonly used staining technique in MMS tissue preparation. MATERIALS AND METHODS Review of literature. Tissue sections were H&E stained using a linear stainer where one reagent container was omitted on each trial run to evaluate microscopic differences in staining quality. RESULTS The chemical nature of H&E staining is discussed, along with commonly encountered problems, pitfalls, and troubleshooting tips. H&E stained sections are presented to demonstrate histologic appearance in the absence of certain reagents. CONCLUSIONS The success of MMS depends on high‐quality tissue sections. The staining process should be optimized to be reproducible and reliable. To readily identify and resolve poor staining quality, a firm understanding of the principles upon which tissue staining is based and its pitfalls is necessary. The authors have indicated no significant interest with commercial supporters.