In vivo intraoral reflectance confocal microscopy of an amalgam tattoo

The majority of oral pigmentations are benign lesions such as nevi, melanotic macules, melanoacanthomas or amalgam tattoos. Conversely, mucosal melanomas are rare but often lethal; therefore, excluding oral melanomas in this setting is crucial. Reflectance confocal microscopy is a non-invasive in vivo imaging system with cellular resolution that has been used to distinguish benign from malignant pigmented lesions in the skin and more recently in the mucosae. However, lesions located posteriorly in the oral cavity are difficult to visually assess and biopsy due to their location. Herein we present a patient with multiple previous melanomas presenting with an oral amalgam tattoo in the buccal mucosa which was imaged using an intraoral telescopic probe attached to a commercially-available handheld RCM. In this case report we describe this novel probe, the first RCM description of an amalgam tattoo and we discuss its differences with the findings described in oral melanomas.