Sellar and suprasellar mixed germ cell tumor mimicking a pituitary adenoma

Endoscopic Endonasal Surgery for Uncommon Pathologies of the Sellar and Parasellar Regions

Endoscopic skull base surgery has become an integral part of the present neurosurgical armamentarium. The pioneering efforts in which the purely endoscopic transsphenoidal approach was introduced have triggered a growing tide of using the endoscopic endonasal procedures for a large variety of skull base lesions. Because of their anatomical peculiarities, lesions of the sellar and parasellar regions lend themselves very well to the endoscopic endonasal approaches. Apart from the common pathological entities, many other less frequent pathologies are encountered in the sellar and parasellar area. In this chapter, we review the surgical technique of the endoscopic endonasal transsphenoidal approach and its extensions applied to a variety of rare and uncommon pathological entities involving the sella turcica and clivus. An overview of these pathological entities is also presented and exemplified.

Small Cell Glioblastoma of the Sella Turcica Region: Case Report and Review of the Literature

BACKGROUND

Glioblastomas in the sellar region are very rare; in most cases, the tumor originates from the optic nerve or optic chiasm. Only 4 cases of sellar glioblastoma with a nonoptic origin have been reported. We present such a case with detailed clinical, imaging, and histopathologic information. We also review similar published cases.

CASE DESCRIPTION

A 42-year-old woman presented with endocrinologic abnormalities, including amenorrhea and lactation, symptoms of diabetes insipidus, and signs of elevated intracranial pressure. Magnetic resonance imaging showed a giant, heterogeneously enhancing lesion involving the intrasellar, parasellar, and suprasellar regions, with hypercellularity and signs of infiltration of adjacent structures. Intraoperative examination revealed the tumor to be independent from the optic pathways, but it showed infiltration of the hypothalamic region. Histopathologic examination demonstrated uniformly packed small cells and negative staining for glial fibrillary acidic protein, which was consistent with a diagnosis of small cell glioblastoma.

CONCLUSIONS

This is the first report of a small cell glioblastoma in the sella turcica region. Glioblastomas in the sellar region with no clear evidence of an optic origin should be viewed as an independent disease entity. The typical characteristics of this tumor indicate it should be considered a rare subtype of glioblastoma. Further accumulation of experience is needed to better differentiate these cases and to offer optimal treatment.

A 23-year-old female with a mixed germ cell tumor of the pituitary infundibulum: the challenge of differentiating neoplasm from lymphocytic infundibuloneurohypophysitis-a case report and literature review

The pathologic spectrum of diseases that infiltrate the pituitary infundibulum includes a broad variety of clinical entities. There are significant differences in the prevalence of these etiologies depending on the age of presentation. Lymphocytic infundibuloneurohypophysitis (LINH) predominates over other causes of infundibular disease in adults over age 21. Differentiating LINH from other causes of infundibular disease can be difficult because the various etiologies often have similar clinical presentations and radiologic imaging characteristics. We report the first case in an adult of a mixed germ cell tumor comprised of germinoma and embryonal cell carcinoma infiltrating the pituitary infundibulum. In our case, a 23-year-old female was initially misdiagnosed as having LINH. She presented with panhypopituitarism and diabetes insipidus, which is the most common initial presentation in both entities. The two diagnoses are difficult to distinguish based on MRI imaging, CSF findings, and histopathological examination. Our case demonstrates the need for close follow-up of patients with isolated lesions of the pituitary infundibulum and reinforces the need for biopsy of an infundibular lesion when progression of disease is demonstrated. In our case, biopsy with comprehensive immunohistochemical staining was the sole means of making a definitive diagnosis.

Sellar Chordoma Presenting as Pseudo-macroprolactinoma with Unilateral Third Cranial Nerve Palsy

We described a 61-year-old female with a sellarchordoma, which presented as pseudo-macroprolactinoma with unilateral third cranial nerve palsy. Physical examination revealed that her right upper lid could not be raised by itself, right eyeball movement limited to the abduction direction, right pupil dilated to 4.5 mm with negative reaction to light, and hemianopsia in bitemporal sides. CT scanning showed a hyperdense lesion at sellar region without bone destruction. Magnetic resonance imaging (MRI) revealed the tumor was 2.3 cm×1.8 cm×2.6 cm, with iso-intensity on T1WI, hyper-intensity on T2WI and heterogeneous enhancement on contrast imaging. Endocrine examination showed her serum prolactin level increased to 1,031.49 mIU/ml. The tumor was sub-totally resected via pterional craniotomy under microscope and was histologically proven to be a chordoma. Postoperatively, she recovered uneventfully but ptosis and hemianopsia remained at the 6th month.

A suprasellar germ cell tumor in a 16-month-old Wagyu heifer calf

A 16-month-old Wagyu heifer calf presented for depression, inappetence, and polyuria/polydipsia. Physical examination revealed that the heifer calf was mentally dull, subjectively small for her age, bradycardic, and hypothermic and had bilateral nasal discharge. Laboratory tests revealed marked serum and cerebrospinal fluid hypernatremia and hyperchloremia with increased cerebrospinal fluid protein. The heifer calf was treated with Ringer solution intravenously for dehydration and electrolyte abnormalities, and with 1 dose each of thiamine and penicillin. Clinical deterioration prompted the owner to elect humane euthanasia. Necropsy revealed a mass lesion in the suprasellar region. Histopathology was consistent with a suprasellar germ cell tumor; the mass stained positive on immunohistochemistry for cytokeratin, vimentin, and c-kit. Suprasellar germ cell tumors have previously been reported in human beings and dogs.