This comprehensive 17-year retrospective analysis of 1,421 Mohs surgery cases evaluated concordance between Mohs surgeons' intraoperative frozen section interpretations and independent dermatopathologist review. The study found a very high rate of agreement, with discordance occurring in only a small percentage of cases, primarily in subtle histologic patterns. The analysis provides robust quality assurance data supporting the reliability of Mohs surgeons' slide interpretation and highlights specific tumor types where enhanced vigilance is warranted.

Mohs surgeon frozen section interpretation shows >97% concordance with independent dermatopathologist review across 1,421 cases.

Discordance is most common with subtle histologic patterns such as desmoplastic or perineural invasion patterns.

These findings support quality assurance protocols including periodic concordance audits in Mohs surgery practices.