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Incomplete Staining Artifact: A Confounding Frozen Section Pathology Artifact Encountered During Mohs Micrographic
Abstract:
The intent of this brief communication is to describe a unique incomplete staining frozen section pathology artifact encountered during Mohs Micrographic Surgery. At the authors’ institution, an amorphous, eosinophilic artifact that obscured cellular architecture was observed multiple times during histological interpretation. It was determined that incomplete tissue staining was likely caused by weak staining, possibly related to an interaction between hematoxylin dye solution and acetone. We adjusted our SLS stain line protocol by adding a 15 second water rinse between the acetone and hematoxylin pots and then compared the old fixation protocol with our new fixation protocol. This artifact, which was regularly found intraoperatively at five separate MMS laboratories has sustainably resolved. Mohs Micrographic Surgery (MMS) is a dermatologic procedure that includes tumor extirpation, tissue grossing, slide preparation, and microscopic histologic interpretation. Tissue grossing and slide preparation are vital components of the MMS procedure. There are many steps throughout tissue processing that can result in frozen section pathology artifacts. Frequently encountered frozen section pathology artifacts include vacuolation of cytoplasm or “freeze artifact,” overstaining and understaining with hematoxylin and eosin, incomplete dehydration, and splaying of collagen in the dermis.1-3 We describe a unique incomplete staining frozen section pathology artifact. J Drugs Dermatol. 2022;21(5):542-544. doi:10.36849/JDD.6722.
Insights
A unique frozen section artifact in Mohs Micrographic Surgery (MMS) was identified as incomplete tissue staining. Adjusting the staining protocol by adding a water rinse resolved this artifact in multiple laboratories.
Area of Science:
- Dermatopathology
- Histotechnology
- Mohs Micrographic Surgery
Background:
- Frozen section pathology artifacts can complicate histological interpretation during Mohs Micrographic Surgery (MMS).
- A specific amorphous, eosinophilic artifact obscuring cellular architecture was repeatedly observed.
- This artifact was suspected to be related to incomplete tissue staining, potentially due to hematoxylin and acetone interactions.
Purpose of the Study:
- To describe a unique incomplete staining frozen section pathology artifact encountered in Mohs Micrographic Surgery.
- To identify the cause of the artifact and implement a protocol adjustment to resolve it.
Main Methods:
- Histological interpretation of frozen sections during Mohs Micrographic Surgery.
- Analysis of staining procedures, specifically focusing on the interaction between hematoxylin and acetone.
- Modification of the SLS stain line protocol by introducing a 15-second water rinse between acetone and hematoxylin steps.
- Comparison of pre- and post-protocol adjustment slide quality.
Main Results:
- The amorphous, eosinophilic artifact was consistently observed across multiple Mohs Micrographic Surgery laboratories.
- The adjusted SLS staining protocol, including the water rinse, successfully resolved the incomplete staining artifact.
- Histological interpretation was no longer obscured by the artifact in the modified protocol.
Conclusions:
- Incomplete tissue staining, potentially due to hematoxylin and acetone interactions, is a identifiable frozen section artifact in Mohs Micrographic Surgery.
- A simple modification to the staining protocol, specifically adding a water rinse, effectively eliminates this artifact.
- Standardizing staining protocols is crucial for accurate intraoperative histological interpretation in Mohs Micrographic Surgery.
