Ex Vivo Line-Field Confocal Optical Coherence Tomography and Ex Vivo Fusion Confocal Microscopy for Lateral-Margin Assessment of Basal Cell Carcinoma in Correlation with Histopathology: A Prospective Pilot Diagnostic-Accuracy Study

Background/Objectives: Rapid optical assessment of freshly excised basal cell carcinoma (BCC) specimens may shorten the interval between excision and margin evaluation. This prospective pilot study estimated the diagnostic performance of ex vivo line-field confocal optical coherence tomography (LC-OCT) for detecting residual BCC at lateral surgical margins, using histopathology as the reference standard. Methods: Fifty-five clinically suspicious lesions from 48 patients were examined at two centers. Results were analyzed for the complete cohort and for a post-training inclusion phase comprising 32 lesions from 31 patients. Overall lesion-level consensus classifications were recorded separately from classifications of the four clock-face quadrants. Lesions with a negative overall LC-OCT assessment and at least one non-evaluable quadrant were classified as indeterminate and excluded from the primary lesion-level analysis. Thirteen lesions also underwent exploratory ex vivo fusion confocal microscopy (evFCM). Results: In the inclusion phase, 125 of 128 quadrants were evaluable. Thirteen true-positive, 106 true-negative, 2 false-negative, and 4 false-positive quadrant results yielded 86.7% sensitivity, 96.4% specificity, and 95.2% accuracy. At the lesion level, 2 of 32 results were indeterminate. Among the remaining 30 lesions, LC-OCT yielded 5 true-positive, 22 true-negative, 2 false-negative, and 1 false-positive results, corresponding to 71.4% sensitivity, 95.7% specificity, and 90.0% accuracy. The evFCM analysis was descriptive because the subset was small and nonconsecutive. Conclusions: Ex vivo LC-OCT showed promising specificity and overall accuracy for assessing lateral BCC margins after training. The limited number of margin-positive lesions, indeterminate results, clustered quadrant data, and absence of systematic deep-margin imaging require cautious interpretation. LC-OCT should not replace histopathological margin assessment on the basis of the present data.