Milad K. Tabatabai

A mainstay treatment of head and neck basal cell carcinoma (BCC) is excision with a fixed surgical margin. Large-scale evaluation of post-surgical margin status is necessary to improve outcomes. This cross-sectional study assessed margin outcomes following excision of head and neck BCCs across Danish healthcare settings, including risk factors for tumour-positive margins. Histopathology records on BCCs excised by all medical specialities between 1 January–31 December 2022 were retrieved from The Danish Pathology Bank. Cases with intraoperative microscopic margin assessment were excluded. Descriptive analyses and multivariable logistic regression determined complete excision proportions and risk factors for positive margins. Including 9,291 BCC excisions in 7,741 patients, the tumour-free proportion was 80.0% (95% CI: 79.2–80.8%). Significant variation occurred by histologic subtype, with tumour-free margins ranging from 60.6% in morpheaform to 83.6% in nodular BCCs. Multivariable analyses also identified morpheaform, micronodular, infiltrating, and superficial subtypes, auricular/postauricular locations, small specimen size, and advancing age as risk factors for tumour-positive margins. The nose was a risk factor in univariable analysis. Simple excision of head and neck BCCs shows notable variation in margin outcomes by patient, tumour, and specimen profile. To minimise recurrence and optimise resources, increased awareness of positive margins is essential.