The diagnostic criteria for basal cell carcinoma (BCC) using optical coherence tomography (OCT) have been described previously, but the clinical value of these findings has been unknown. Objective The aim of this study was to investigate the diagnostic value of OCT for BCC in a typical clinical setting. The primary efficacy endpoint was a diagnosis of BCC for each lesion. Secondary endpoints were the diagnosis of other possible conditions.
This was an observational, prospective, multi-centre study in which consecutive patients with non-pigmented pink lesions suspicious for BCC underwent clinical assessment, dermoscopy, and OCT with the diagnosis recorded at each stage. Once all diagnoses had been recorded, histological results were disclosed. One hundred and sixty-four patients with 256 lesions were recruited. Histology was missing for 21 lesions, leaving 235 lesions in 155 patients for analysis.
Sixty per cent of lesions (141/235) were identified as BCC by histology. A slight increase of sensitivity was noted following OCT, which did not reach statistical significance. Specificity increased significantly from 28.6% by clinical assessment to 54.3% using dermoscopy and to 75.3% with the addition of OCT (p<0.0001). Positive predictive value for diagnosis of BCC using OCT was 85.2% (95% CI: 78.6 – 90.4); negative predictive value was 92.1% (95% CI: 83.6 – 97.0). The accuracy of diagnosis for all lesions increased from 65.8% with clinical evaluation to 76.2% following additional dermoscopy and to 87.4% with the addition of OCT.
OCT significantly improved diagnostic specificity for BCC compared to clinical assessment and dermoscopy alone.