Use of In Vivo Optical Coherence Tomography (OCT) for Surgical Margin Assessment in Keratinocyte Carcinomas: A Systematic Review

Background/Objectives: Keratinocyte carcinomas (KCs), including squamous cell carcinomas (SCCs) and basal cell carcinomas (BCCs), are the most common malignancies worldwide. Accurate delineation of surgical margins is essential to ensure oncological control while preserving favourable aesthetic outcomes. Optical coherence tomography (OCT) is a non-invasive, real-time, high-resolution technique that may facilitate preoperative and intraoperative margin assessment. This systematic review aims to analyse existing evidence on the use of in vivo OCT in the assessment of surgical margins in KC. Methods: This systematic review was conducted in accordance with the PRISMA guidelines. The articles included were retrieved from the PubMed, Web of Science, Scopus and EBSCO databases. The search was limited to studies published between 2010 and November 2025. The inclusion criteria were the application of in vivo OCT as an adjunctive method in the surgical excision of KC. A total of 11 studies involving 303 patients met the inclusion criteria. OCT was used preoperatively, intraoperatively, combined pre- and intraoperatively and both pre-, intra- and postoperatively, with most studies focused on margin delineation by itself. Results: Agreement between OCT and histopathology ranges from 84% to 95.5%. Surgical benefits were observed in both conventional surgery and Mohs micrographic surgery, including reduction in MMS stages (1.89 to 1.23), fewer stages required, and narrower excision margins. Conclusions: Based on data analysis, it may be assumed that in vivo OCT may have potential in non-invasive margin assessment in the surgical treatment of KC. The available evidence is limited by the heterogeneity of protocols and devices and variability between lesion types, as well as the small sample sizes and limited comparability. Further research should focus on randomised multicentre trials involving large cohorts, cost–benefit analysis and evaluation of operator-dependent variability.