Brain Pathology Case of the Month - October 2015

Contributed by Zhang Xie-jun, MD1*, Huang Guo-dong, MD, PhD1*, Ji Tao, MD1, Zhang Xiao-biao, MD2, Liu Wen-lan, MD, PhD3 and Li Wei-ping, MD1
   *Both authors contributed equally to preparing the paper
1Department of Neurosurgery and 3Central Laboratory of Shenzhen Second People's Hospital, The first affiliate hospital of Shenzhen University, Shenzhen, Guangdong, 518000, China
   2Department of Neurosurgery, Zhongshan Hospital Fu Dan University, Shanghai, China, 200032


CLINICAL HISTORY

A 30-year-old female has experienced amenorrhea and progressive loss of vision for four years. Physical examinations were normal except bitemporal hemianopsia revealed by ophthalmic examination. Preoperative neuroendocrine examinations showed a mild hyperprolactinemia of 72.3ng/ml (normal range, 2.8 ng/ml-29.2 ng/ml). MRI scan revealed a 31 mm × 34 mm × 31 mm well-circumscribed roundness mass in the suprasellar region, with intermediate signal intensity on T1-weighted images, intermediate to slightly increased signal intensity on T2-weighted images, and homogeneous enhancement with gadolinium administration with obviously homogeneous enhancement after gadolinium administration (Fig. 1). Extended endoscopic endonasal transsphenoidal approach was chosen to resect the tumor. Intraoperatively, we encountered active bleeding, however, the bleeding stopped after the tumor was completely resected. Postoperative, the patient had serious diabetes insipidus and electrolyte disturbance. Blood sodium was as high as 190mmol/l (normal range, 135 mmol/L-145 mmol/L). After comprehensive treatment, the diabetes insipidus was cured and blood sodium became normal. Three months after endoscopic surgery, MRI examination revealed that the tumor was completely removed (Fig. 2).

MICROSCOPIC PATHOLOGY

The tumor tissue was fixed by formalin and processed with standard paraffin technique. Routinely stained (H&E) examination revealed that the neoplasm was composed of bipolar spindle cells, arranged in interlacing fascicles or storiform pattern with rich cytoplasm (Fig. 3). Immunohistochemistry showed that the tumor cells were negative for all anti-hormonal antibodies, but positive for GFAP (Fig. 4), S-100 (Fig. 5), Vim (Fig. 6), EMA (Fig. 7), and the Ki-67 proliferation index was about 5% (Fig. 8). What is your diagnosis?

FINAL DIAGNOSIS


International Society of Neuropathology