Maxillary Sinus Natural Killer/T-Cell Extranodal Lymphoma Mimicking a Dentoalveolar Abscess

Figure 4

Histopathological features: in (a), the histologic section from the lesion biopsy sample shows a diffuse and permeative infiltrate of small to medium-sized atypical lymphocytes (H&E, ×100); in (b), an evident angiocentric and angiodestructive growth pattern is represented (H&E, ×400). Immunohistochemical and in situ hybridization reactions: in (c), the neoplastic cells show immunopositivity for CD45 (×400); in (d), immunopositivity (partial/weak) for CD3 (×400); in (e), immunonegativity for CD20 (×400); in (f), immunopositivity for CD56 (×400); in (g), immunopositivity (cytoplasmic granules) for TIA1 (×400); in (h), Ki67 index (×400); and in (i), positive nuclear labeling for in situ hybridization for EBV (×400).

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