Primary dermal melanoma (PDM) is a rare variant of cutaneous melanoma confined to the dermis and/or subcutis. PDM comprises between 0.4% and 0.9% of melanoma cases, with reports in the literature remaining scarce. PDM histologically mimics metastatic melanoma but is associated with a more favorable prognosis.

PDM primarily affects middle-aged adults, usually younger than 60 years, and its distribution is typically truncal, although head, neck, and limb involvement have been reported. It has been suggested that PDM may originate from dermal melanocytes, embryological migration remnants, or aberrations, as well as appendage-associated nonepidermal melanocytes.

Clinical cues favoring a PDM diagnosis include the absence of previous history of primary visceral and cutaneous melanoma, the absence of a spontaneously resolving melanocytic lesion, and the absence of nodal, visceral, and central nervous system metastases.

Five-year survival rates of PDM have been reported to be 73%-100%, and this includes patients with tumors with higher initial Breslow depth. However, up to 30% of patients have been reported to develop local recurrences (including multiple recurrences), nodal involvement, in-transit metastases, and distant metastases.