MARY S.STONEMDSOONBAHRAMIMDCARRIE ANN R.CUSACKMDSENAIT W.DYSONMDMOLLY A.HINSHAWMDVINCENTLIUMD
Fresh-frozen and permanent sections were analyzed and revealed a neoplasm composed of alveolar nests separated by a dense fibrovascular stroma. These nests showed a biphasic cell population of large, epithelioid, polygonal cells admixed with small, basophilic, rounded, neuroblastlike cells (Figure 2). The large cells were situated more at the periphery of the nests and had abundant eosinophilic cytoplasm containing melanin pigment, which gives MNTI its characteristic blue-black appearance. The small cells, more centrally positioned, had scant cytoplasm and hyperchromatic nuclei. Small neoplastic cells stained positively for synaptophysin, and the large neoplastic cells expressed the HMB-45 antibody (Figure 3) and pancytokeratin markers AE1 and AE3. Both cell types tested positive for neuron-specific enolase. The histologic and immunohistochemical findings confirmed the diagnosis of MNTI.
Rapidly Growing Gingival Mass in an Infant—Diagnosis. Arch Dermatol. 2010;146(3):337-342. doi:10.1001/archdermatol.2010.9-b