Figure 7.

Melanoma ex BAP1 inactivated nevus; relapse, initial lesion at age 11(hematoxylin, phloxin, safranin stain). (A): Low-magnification silhouette: compound melanocytic proliferation with dense dermal nodular areas including pigmented clones. (B): Intermediate view of a cellular area with admixed small and large cells. (C): Close-up view of a deep dermal nodule with mixed small nevocytoid and large epithelioid melanocytes. A few of them show a pigmented cytoplasm; mitotic figure (arrow). (D): BAP1 immunohistochemistry (clone C4; 1/50): loss of nuclear staining with positive controls of endothelial cells. (E): Ki67 immunohistochemistry: variable dermal staining with clonal areas showing a 10% positivity.