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Washington University Experience | NEOPLASM (SELLAR) | TTF-1-positive sellar tumor - Pituicytoma | 3P7 W23-2669 Skinner H (Case 3) Brain tumor_013 - Copy

One of the plasma cells in the inflammatory infiltrate is shown. (electron micrograph) ---- Comment: The collective morphological and immunohistochemical features are consistent with a diagnosis of a posterior pituitary neoplasm, TTF-1 positive. The differential includes spindle cell oncocytoma, granular cell tumor and pituicytoma which are often considered part of a continuum. Given the extent of GFAP positivity a pituicytoma is slightly favored over the other two entities.

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