The Diagnostic Accuracy of Ex Vivo Confocal Laser Scanning Microscopy for Basal Cell Carcinoma: A Systematic Review and Meta-analysis.

This systematic review and meta-analysis evaluated available data on the diagnostic accuracy of ex vivo confocal laser scanning microscopy (EVCM) for the diagnosis of basal cell carcinoma (BCC) in tissue specimens and for margin assessment in micrographic surgery, using conventional histopathological analysis as reference standard. MEDLINE and Embase were systematically searched in November 2024 in accordance with PRISMA guidelines to identify diagnostic accuracy studies evaluating EVCM for BCC. Pooled sensitivity and specificity were estimated using bivariate random effects models. Sixteen studies comprising 1,387 specimens were included. The pooled mean EVCM acquisition time was 7.0 min (95% confidence interval [CI]: 5.3-9.4). For BCC diagnosis in tissue specimens, pooled sensitivity was 91.4% (95% CI: 85.9-94.9) and pooled specificity was 91.1% (95% CI: 79.2-94.5). Regarding margin assessment, pooled sensitivity and specificity were 79.5% (95% CI: 65.0-89.0) and 92.2% (95% CI: 85.5-95.9). In conclusion, EVCM shows high sensitivity and specificity for BCC diagnosis in tissue specimens and may selectively replace conventional histology when rapid diagnosis is desired. For margin assessment, EVCM has high specificity but moderate sensitivity. Therefore, conventional histology should still be considered as a subsequent step, particularly after the final excision stage of stepwise micrographic surgery.