Background: Melanocyte colonization of breast carcinoma cells may occur in those tumors that breach the epidermal-dermal interface. The resultant melanin deposition in tumor cells rarely leads to clinical pigmentation of the tumor. Typically, selective staining methods are required to detect the pigment.
Observation: The authors describe a 60-year-old woman with a history of mammary carcinoma and an irregularly pigmented nodule with peripheral globules and a blue-white veil on dermoscopy, which was a clinical and dermoscopic mimic of malignant melanoma.
Conclusions: Awareness of melanocyte colonization of non-melanocytic tumor cells and the dermoscopic-histologic correlations can aid in avoiding a potential pitfall, and emphasize the importance of such relationships, when using this tool.