Impact of line-field optical coherence tomography in preoperative margin assessment of head and neck basal cell carcinoma: a cohort study

: In head-and-neck basal cell carcinoma (BCC), accurate preoperative delineation of lateral tumour margins remains challenging. Line-field confocal-optical coherence tomography (LC-OCT) offers real-time, high-resolution imaging that may improve surgical planning. This study evaluated the impact of preoperative LC-OCT on oncologic and procedural outcomes, focusing on lateral positive margins.A mixed prospective-retrospective cohort study was conducted, comparing BCC cases treated after LC-OCT implementation (2023-2024) with historical controls (2018-2021). Lesions with unclear clinical or dermoscopic margins underwent LC-OCT-guided mapping. Primary outcomes were positive histological margins and recurrence; secondary outcomes included time to surgery, operative time, frozen section use, reconstruction, and minimum lateral margin distance. Multivariable logistic regression adjusted for group, age, tumour size, H-zone location, presentation, histologic subtype, and pT stage.A total of 102 patients were included (LC-OCT n = 23; controls n = 79). H-zone distribution was comparable between groups (69.5% vs 53.2%, P = 0.50). Positive margins occurred in 19.0% vs 24.6% (P = 0.772), and recurrence in 0% vs 5.2% (P = 0.573). Median time to surgery was longer with LC-OCT (48 vs 34 days, P = 0.016), while operative time was shorter (55 vs 95 minutes, P = 0.013).In multivariable analysis, H-zone location (aOR 3.96, P = 0.041) and aggressive histology (aOR 6.39, P = 0.015) predicted lateral positivity, whereas LC-OCT did not (aOR 1.61, P = 0.565; AUC 0.774).LC-OCT did not independently reduce lateral positive margins but may support precision mapping, at the cost of longer treatment timelines. Prospective studies with standardized workflows are warranted.