Spindle cell oncocytoma of the adenohypophysis: a clinicopathological analysis of two cases

WU Long-bo; ZHANG Xuan-hong; HUANG Liang-liang; LI Heng; WU Hai-bo

doi:10.3969/j.issn.1007-8096.2018.03.006

Abstract：Objective To explore the clinicopathologic features,immunohistochemical and ultrastructural features of spindle cell oncocytoma (SCO) of the adenohypophysis,with emphasis on diagnosis and differential diagnosis.Methods The clinical characteristics,radiological appearance,pathological,immunohistochemical and ultrastructural findings were analyzed,the literatures were also reviewed.Results Two cases of SCO of the adenohypophysis occurred in patients at the age of 44 years and 64 years,respectively,who presented with visual field defect in both cases.MRI showed a solid sellar mass with suprasellar extension.Histologically,the tumors were composed of interwoven fascicles or whorls of spindle cells exhibiting abundant eosinophilic cytoplasm.The epithelioid cells were scattered or distributed in different ranges,and there was a transition between epithelioid cells and spindle cells.The tumor cells showed immunoreactivity for vimentin,S-100,EMA,TTF-1 and gelactin 3,but they were negative for CK,GFAP,INI1,Syn,CgA and anterior pituitary neuroendocrine marker.Ultrastructurally,intermediate junctions and a few desmosomes were seen,as well as foci of bundles of intermediate filaments.Conclution SCO of the adenohypophysis is a rare sellar tumor with a tendency to recur.Intergrative analysis of clinical,radiology,histomorphology,immunohistochemistry and ultrastructural changes will help accuracy diagnosis of SCO.