This study surveyed immunohistochemistry (IHC) utilization patterns in Mohs micrographic surgery, examining which stains are used most frequently, for which tumor types, and how IHC impacts surgical outcomes. The analysis revealed increasing adoption of IHC in Mohs practice, particularly MART-1/MelanA for melanoma, cytokeratin stains for poorly differentiated SCC, and BerEP4 for morpheaform BCC. The study provides evidence-based guidance on when IHC adds clinical value versus standard H&E-only interpretation.

IHC use in Mohs surgery is increasing, with MART-1/MelanA, cytokeratins, and BerEP4 as the most commonly used stains.

MART-1 immunostaining improves margin assessment accuracy for melanoma-in-situ and lentigo maligna treated with Mohs.

IHC is most valuable for tumors with subtle infiltrative patterns where H&E interpretation alone may be insufficient.