Early diagnosis of basal cell carcinoma-a cutaneous neoplasia with high incidence-can bring great benefits to the patient. Often, slightly pigmented lesions, small initial lesions, and superficial lesions can represent a clinical and dermoscopic diagnostic challenge for not having the typical findings of this neoplasia. In such cases, optical coherence tomography-a promising technology in dermatology-is an auxiliary, non-invasive resource that can be incorporated into the clinical practice.

Keywords: BASAL CELL CARCINOMA, DIAGNOSTIC IMAGING, OPTICAL COHERENCE TOMOGRAPHY.

Recurring nevus or pseudomelanoma is a benign melanocytic lesion that appears in the same location after an incomplete surgical removal of nevi. These pigmented melanocytic lesions can in some cases be a diagnostic challenge when examined through dermoscopy, especially if there is a clinical history of growth or recurrence of the lesion, as happens with the recurrent nevus phenomenon. Confocal reflectance microscopy is an in vivo non-invasive imaging technique with high histomorphological resolution of the skin that can be used to differentiate between benign and malignant lesions, increasing the in vivo diagnostic accuracy. Nonetheless, in some cases only the histological and immunohistochemical examinations of the complete lesion can clarify the diagnosis.

Keywords: CARCINOMA, BASAL CELL; EPIDEMIOLOGY; SKIN NEOPLASMS; PATHOLOGY; DERMATOLOGY