Brain Pathology Case of the Month - August 2012

Contributed by Alexandre do Nascimento, MD1; Luana A. Maranha, MD2; Renata A. Corredato, MD2; João Cândido Araújo, MD2; Luiz F. Bleggi-Torres, MD, PhD1,3
1Department of Pathology and 2Neurosurgery Unit, Hospital de Clínicas; 3Institute Pelé-Pequeno Príncipe, Curitiba, Brazil.


A 33 year old female patient presented in June 2009 with progressive loss of vision for the last 12 months plus occasional episodes of headache. In the last 3 months her vision deteriorated even further with progressive temporal amaurosis, and she started having depression with episodes of extreme anxiety. She developed amenorrhea since her last pregnancy 8 years ago with episodes of galactorrhea. CT scan (Figure 1) showed a mass lesion in the sellar region suggestive of meningeoma or pituitary adenoma. She received bromocriptine 2.5mg/day with no reduction of the lesion. She developed panhypopituitarism with normal levels of prolactin. Further MRI showed a large lesion infiltrating cavernous sinuses and compressing the optic nerve. Transsphenoidal surgical treatment was performed. Two months after the first operation she returned to hospital with complete bilateral amaurosis and a new MRI showed residual lesion. A new sub-frontal neurosurgery was performed and most of the lesion was resected. The patient developed diabetes insipidus but remains under control.


Several fragments of gray elastic tissue were received for histological examination. Sections showed, apart from small fragments of normal pituitary, the presence of tumor cells arranged in nests and lobules separated by a delicate vascular network (Figure 2). Tumor cells were large with clear or slightly eosinophilic cytoplasm (Figure 3) with moderate nuclear pleomorphism with vesicular nuclei and occasional nucleoli. Mitotic figures were rare and there was no necrosis. Reticulin stains (Figure 4) demonstrated a characteristic pattern. Immunohistochemistry showed positivity for chromogranin A, neuron-specific enolase and synaptophysin (Figure 5) with a few cells positive for S100. Ki67 was 1-2%. Vimentin was positive in the vascular network. All pituitary hormonal antibodies were negative as well as GFAP, AE1/AE3, p53 and EMA.


International Society of Neuropathology