Melanoma Arising in Tattoos: A Case Series and Scoping Review of the Literature

Background/Objectives: The prevalence of tattoos has risen globally in recent decades, ranging from 10% to 29%. Although rare, melanomas arising within tattoos are challenging for dermatologists due to the complexities in clinical and dermoscopic evaluation. In this article, we report two cases of melanoma on tattoos, review the reported cases in the literature, and examine the role of reflectance confocal microscopy (RCM) in improving the diagnosis of melanoma on tattooed skin. Methods: We conducted a systematic literature search on Medline/Pubmed for the period from the inception of the databases to 31 October 2024, using the Mesh major topics 'melanoma' AND 'tattoo' OR 'tattoo skin tumor'. Out of the 268 citations identified by our search, 37 studies met the eligibility criteria. Results: In total, 43 cases of melanoma arising on tattooed skin were identified, to which we add our 2 cases, bringing the total to 45. The most common locations were the upper limbs (53%) and trunk (38%), predominantly arisen on black and blue tattoos. Of 40 cases with known depth of invasion, 4 were in situ and 36 invasive, with a mean Breslow thickness of 2.7 mm. Seven patients had a positive sentinel lymph node. Of 16 cases with an available horizontal diameter, 12 melanomas had a diameter of >= 1 cm. Conclusions: The limited cases of ''melanoma on tattoos" reported in the literature suggest a coincidental association rather than a direct causal link. Nevertheless, increased awareness among patients and tattoo artists about potential risks and preventive measures may enhance the management of melanocytic lesions in tattooed individuals. Lastly, integrating reflectance confocal microscopy with dermoscopy increases the overall diagnostic accuracy for melanoma, enhancing the identification of pigmented and non-pigmented skin lesions.