Primary Pulmonary Meningioma Simulating a Pulmonary Metastasis

Figure 2

Histological features of the case (surgical lung biopsy specimen). (a) Microscopic examination revealed a well-defined nodule that compressed surrounding lung parenchyma. Hematoxylin-eosin (HE) 40x. (b) At high power view, the tumor includes nests of round to spindle shape cells that present focal whorls pattern. The tumor cells showed clear cytoplasm and round and oval nuclei with delicate chromatin distribution and some intranuclear inclusions. Mitotic figures are not present. Hematoxylin-eosin (HE) 200x. (c) In immunohistochemistry study, the tumor cells showed positive staining for PR (100x) and (d) CD56 (100x).

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