In Vivo Optical Coherence Tomography for the Detection, Subtyping, and Margin Assessment of Facial Basal Cell Carcinoma: A Comparative Study with Histopathology

<b>Background:</b> Basal cell carcinoma (BCC) is the most common skin cancer, with several subtypes that vary from one another in biological behaviour and therapeutic consequences. The aim of the study was to evaluate in vivo OCT diagnostic accuracy to detect and subtype facial BCCs, using histopathology as the gold standard. <b>Patients and Methods:</b> This single-centre, prospective, diagnostic accuracy study was carried out on 136 patients who were presenting with a total of 220 clinically suspicious facial lesions for BCC. All lesions were imaged by OCT before their surgical excision. OCT findings were compared to the histopathological results in the respect of detection of BCC, subtype, tumour depth, and margin status. <b>Results:</b> OCT showed an excellent diagnostic performance for the detection of BCC in general: sensitivity, 96.8%; specificity, 98.2%; and accuracy, 97.5%. The AUC for the detection of BCC was 0.97. Subtype sensitivity for OCT was highest for superficial, 93.1%, and nodular BCC, 92.1%, and marginally lower for micronodular, 89.3%, and infiltrative subtypes, 90.0%. Depth measurements of OCT-derived tumour strongly correlated with those obtained by histopathology: mean depth, 2.3 ± 0.9 mm for OCT versus 2.2 ± 0.8 mm for histopathology; <i>p</i> = 0.08. <b>Conclusions:</b> The performed OCT showed very good agreement in the detection, subtyping, and preoperative assessment of BCC facial lesions. In addition to its non-invasive characteristics, its robustness regarding the evaluation of tumour depth and margins makes OCT very promising for improved surgical planning by reducing unnecessary excisions.