Pituicytoma: Report of two cases

Abstract

Abstract. This report describes two cases of pituicytoma. The two patients were female and presented with visual complaints, diabetes insipidus, headaches and menstrual disorders. The imaging characteristic was an intrasellar or suprasellar mass, and one mass originated in the pituitary stalk. The mass showed homogeneous enhancement with contrast administration. A hematoxylin and eosin stain showed a compact structure consisting of elongated, bipolar spindle cells arranged in interlacing fascicles or assuming a storiform pattern. Immunohistochemically, the tumor showed diffuse strong expression of S-100 protein, vimentin and epithelial membrane antigen, and glial fibrillary acidic protein was focally positive. The pituicytoma may have originated in the pituitary stalk and presented with diabetes insipidus, and the differential diagnosis should be compared with the pituitary stalk mass. Bleeding during resection was moderate, and surgery was regarded as the first choice of treatment for pituicytomas.

A 45‐year‐old woman with tumor in the sellar region

“…Our present case showed remarkable nuclear pleomorphism, which has been rarely described in the previous literature 11,12 . The immunohistochemical profile of a pituicytoma is characterized by diffuse S‐100 protein and vimentin immunoreactivity and varying GFAP and EMA expression 2,13,14 . No immunoreactivity is observed for neuroendocrine and pituitary hormone markers.…”

“…11,12 The immunohistochemical profile of a pituicytoma is characterized by diffuse S-100 protein and vimentin immunoreactivity and varying GFAP and EMA expression. 2,13,14 No immunoreactivity is observed for neuroendocrine and pituitary hormone markers. The Ki-67 labeling indices are very low (ranging from 0.5% to 2%).…”

Oncocytic Lesions of the Neuroendocrine System

“…The null cell adenomas are chromophobic and may show varying degrees of oncocytic change, whereas, the oncocytomas are comprised mainly of oncocytes. 153,154,[157][158][159] By light microscopy, pituicytomas show bipolar spindle cells with round to elongate nuclei with oncocytic cytoplasm and are organized in interlacing fascicles/storiform pattern 157,160 (Fig. Oncocytomas show similar electron microscopic profile to null cell adenomas except that they contain abundant mitochondria which occupy the greater part of the cytoplasm in >50% of the tumor cells.…”

A rare case of pituicytoma-related hyperprolactinemia due to mass effect on infundibular stalk—Case report

“…The tumour can often simulate a pituitary adenoma and is also linked with hormonal disorders [ 4 , 5 ]. Other clinical manifestations involve compression of the optic chiasm, infundibulum or posterior pituitary gland causing blurring of vision; headache; and characteristics of hypopituitarism such as fatigue, mildly elevated serum prolactin, menstrual irregularities and decreased libido [ 6 ]. The tumour is typically a dense and defined mass lesion of the sellar and suprasellar spaces on magnetic resonance imaging (MRI).…”