The reflectance confocal microscopy in diagnosis of recurrent basal cell carcinoma

Background: Reflectance confocal microscopy (RCM) is very valuable, non-invasive diagnostic tool in the diagnosis of basal cell carcinoma (BCC). Objective: We aimed to demonstrate the positive predictive value (PPV), negative predictive value, sensitivity and specificity of RCM and dermoscopic features in recurrent BCC. Methods: The 152 entire lesion sites in 128 patients with BCC were evaluated by clinical examination, dermoscopy and RCM imaging techniques. Biopsy was performed from 46 lesions if there was at least one of the clinical findings or at least one of the diagnostic criteria of BCC with dermoscopy or RCM examination. Histopathological examination was considered as a gold standard for the diagnosis of recurrence BCC. Results: Recurrence was observed in 29 cases (63%). In the dermoscopic examination, arborizing telangiectasia and blue-grey globules were found to be statistically significantly correlated with BCC recurrence (p<0.05). The specificity and PPV of nucleated corneocytes in the stratum corneum and polarisation of elongated nuclei in the epidermis was 100%. PPV of streaming of aggregated tumour cells and variable refractile stroma was 92% with RCM examination. Conclusion: RCM is a diagnostic tool with a high PPV, sensitivity and specificity for the diagnosis of recurrence of BCC lesions.