Nail Apparatus Melanoma: Current Management and Future Perspectives

Nail apparatus melanoma (NAM) is a rare type of cutaneous melanoma that belongs to the acral melanoma subtype. NAM is managed principally in accordance with the general treatment for cutaneous melanoma, but there is scarce evidence in support of this in the literature. Acral melanoma is genetically different from non-acral cutaneous melanoma, while recently accumulated data suggest that NAM also has a different genetic background from acral melanoma. In this review, we focus on recent advances in the management of NAM. Localized NAM should be surgically removed; amputation of the digit and digit-preserving surgery have been reported. Sentinel lymph node biopsy can be considered for invasive NAM for the purpose of accurate staging. However, it is yet to be clarified whether patients with metastatic sentinel lymph nodes can be safely spared completion lymph node dissection. Similar to cutaneous melanoma, immune checkpoint inhibitors and BRAF/MEK inhibitors are used as the first-line treatment for metastatic NAM, but data on the efficacy of these therapies remain scarce. The therapeutic effects of immune checkpoint inhibitors could be lower for NAM than for cutaneous melanoma. This review highlights the urgent need to accumulate data to better define the optimal management of this rare melanoma.