'Ectopic' suprasellar type IIa PRL-secreting pituitary adenoma.

BACKGROUND: Ectopic pituitary adenomas (EPAs) are rare, and the suprasellar cistern seems to be the most common location. At this time, no detailed original classification, diagnosis, or treatment protocols for suprasellar pituitary adenomas (SPAs) have been described. CASE DESCRIPTION: A 19-year-old man showed visual disturbances and lack of libido for 3 years, he suffered a sharp decline in vision with only light perception in the last week. Magnetic resonance imaging scans revealed a large suprasellar cystic lesion with a normal pituitary in the sella turcica. Endocrinological findings showed an extremely high prolactin level of 1250 ng/mL. Because of the sharp decline in vision, the patient underwent total removal of the suprasellar lesion using a transfrontal interhemispheric approach. The tumor pedicle originated in the lower pituitary stalk without any connection to the anterior pituitary gland in the sella turcica, while the diaphragma sellae was incomplete. Clinical and endocrinological cure criteria were fulfilled and postoperative pathology confirmed a prolactin-secreting pituitary adenoma. CONCLUSION: Ectopic suprasellar pituitary adenomas (ESPAs) are extremely rare intracranial extracerebral tumors. SPAs can be classified into three types according to their origin and their relationship with surrounding tissue. Only type III is theoretically a true ectopic, based on previous reports. Thus, ESPAs are uncommon compared to other EPAs. Our case is the first reported case of a type IIa 'E'SPA and the first description of this subtype classification until now. The pars tuberalis may be different from the pars distalis, and each subtype of adenohypophyseal cells may have different migration characteristics, which leads to different proportions of each hormone-secreting subtype in SPAs and EPAs. Transsphenoidal surgery is minimally invasive, but transcranial surgery may remain a universal option for the treatment of suprasellar lesions.

The clinicopathological features of pituicytoma and the differential diagnosis of sellar glioma.

Pituicytoma is rare and difficult to diagnose. This study explored the clinicopathological features, immunophenotype and differential diagnosis of pituicytoma. We compared 11 cases of pituicytoma and 26 cases of sellar glioma (16 pilocytic astrocytomas, four diffuse astrocytomas, three pilomyxoid astrocytomas, and three third ventricle chordoid gliomas). The 11 pituicytoma cases involved six men and five women (age: 33-65 years). Three of the 11 patients experienced recurrence due to a residual tumor, and one patient underwent three surgeries during a 6-month period. Imaging findings revealed tumors were in the intrasellar region (four cases), suprasellar region (four cases) and intra-suprasellar regions (three cases). The tumor diameters were 1.3-3.8 cm, and the preoperative diagnoses were pituitary adenoma, craniopharyngioma and meningioma. The tumors were solid and contained spindle or slightly chubby cells that were densely arranged with visible cleft-like or expanded sinusoid structures. The cells had vague boundaries, circular nuclei, fine chromatin, and a small nucleolus. Immunohistochemical staining of the pituicytomas revealed positive expression of thyroid transcription factor-1 (TTF-1) and S-100 protein (S-100), positive focal expression of glial GFAP;(five of 11 cases), and negative oligodendrocyte transcription factor 2 (Olig2), CD34 and neurofilament expression. The Ki67 index was 6% in one case and 1-2% in the other cases. Unlike pituicytoma, most sellar glioma cases exhibited GFAP and Olig2 expression, and negative TTF-1 expression. Third ventricle chordoid gliomas expressed TTF-1, GFAP and CD34, and were negative for Olig2. Our results indicate that pituicytoma typically involves dense arrangements of spindle or slightly chubby cells. The morphology is occasionally atypical, with ependymoma-like or meningioma-like structures, and occasionally exhibits pilomyxoid degeneration. Abundant sinusoids are characteristic of hemorrhagic tumors. The dense spindle cell arrangement is a relatively specific morphology, and staining for GFAP, TTF-1, Olig2 and CD4 may help differentiate pituicytoma from sellar glioma.

Microsurgical anatomy of membranous layers of the pituitary gland and the expression of extracellular matrix collagenous proteins.

BACKGROUND: There are several reports about the microanatomical and histological features of sellar and parasellar membranous structures and clinical studies about MMP proteinase as a predictive factor. However, studies on collagen contents of sellar and parasellar membranous structures are limited. We demonstrated the membranous structures surrounding the pituitary gland and defined extracellular matrix (ECM) collagenous proteins, collagen I-IV expression patterns of sellar and parasellar connective tissues. METHODS: The study was carried out on ten fresh postmortem human bodies at the Forensic Medicine Institution. Cavernous sinuses were resected with sellar structures and were stored at -80°C liquid nitrogen tanks. Medial wall of the cavernous sinus, pituitary capsule and pituitary tissue samples were obtained for RT-PCR. Opposite side specimens were used for histological and immune staining studies. Collagens I-IV were studied by immunohistochemical and reverse transcription polymerase chain reaction (RT-PCR) methods. FINDINGS: The pituitary capsule and medial wall were identified as two different structures. The fibrous membrane, as the third membrane, was identified as staying whole in eight of ten specimens. Increased type IV collagen was determined in the pituitary gland, medial wall and pituitary capsule, respectively, in both RT-PCR and immunhistochemical studies. Immunhistochemical studies revealed that collagen I was strongly expressed in both the medial wall and pituitary gland. CONCLUSION: Increased type IV collagen was detected especially in pituitary tissue, the medial wall and the pituitary capsule by immune staining and RT-PCR. Type IV collagen was considered to be an important factor in the progression of adenoma and invasion.

Folliculo-stellate cells of the human pituitary as adult stem cells: examples of their neoplastic potential.

Two unique, formerly unrecorded sellar neoplasms were observed in two women of 60 and 63 years of age. One lesion consisted of small epithelial cells and the other was a large-cell oncocytic tumor, yet they had the same simple cytoplasmic organization with dominance of polyribosomes and a sprinkle of glycogen. Striking markers shared by the neoplasms: (1) network of typical pituitary follicles, and (2) unexpected similarity to fetal human pituitary tissue at different gestational ages of 6 and 10-12 weeks. The latter showed appreciable endocrine differentiation. The assumed parent cell is the folliculo-stellate cell as pluripotent adult stem cell.

Expression of extracellular matrix-proteins in perisellar connective tissue and dura mater.

PURPOSE: To describe the pattern of expression of extracellular matrix (ECM) proteins in perisellar connective tissue. METHODS: Dural and perisellar specimens from ten individuals were investigated immunohistochemically for collagens I to IV, tenascin, fibronectin, elastin, laminin, and vitronectin. FINDINGS: Collagen I and III and fibronectin were strongly expressed and collagen IV, tenascin, and vitronectin were moderately expressed in the boundaries of the sella and around the CS. In six of nine specimens from the anterior boundary of the sella, and in 11 of 19 samples from the lateral boundary of the sella (medial wall of CS), two different layers could be detected by the expression of different ECM proteins. None of the antigens generally allowed differentiation between two layers of the pituitary envelope. CONCLUSIONS: The pituitary boundary may consist of a single or a double layer, infrequently differentiated from each other by the expression of different ECM proteins.

[Two cases of sellar chordomas. Ultrastructural and histochemical study (author's transl)]. / Deux observations de chordome de la selle turcique. Etude ultrastructurale et histochimique.

Two cases of sellar chordomas are reported, with ultrastructural and histochemical study. The embryological origin and the histochemical data are discussed. The question of chondroid chordomas is evoked and the results of the ultrastructural study are interpreted on the basis of the cases hitherto reported. Special attention is called to the methods for the detection of polysaccharides by electron microscopy in such proliferations. Tissue culture seems to be able of providing a good information as to the secretory activity of the chordomas located at the skull base.

The value of the thyrotropin-releasing hormone test in patients with prolactin-secreting pituitary tumors and suprasellar non-pituitary tumors.

The prolactin (PRL) response to thyrotropin-releasing hormone (TRH) (delta PRL) was normal in 7 (18%) of 38 patients with clinical evidence of a prolactinoma. A negative percentage correlation between basal PRL and delta PRL was found (P less than 0.05), but a percentage correlation between tumor size and delta PRL was absent. In a survey of literature concerning 548 patients, delta PRL after TRH administration amounted to 100% or more of the basal value in 11% of patients with clinical evidence of a prolactinoma and in 9% with an adenoma proven by surgery. Hyperprolactinemia was also present in 12 of our 21 patients (57%) with suprasellar tumors not related to pituitary tumors. In 7 of 11 of these hyperprolactinemic patients (64%), the PRL response to TRH was decreased. In conclusion, the TRH test may be helpful but is not decisive in the diagnostic work-up of hyperprolactinemia patients.

[Pantopaque-cisternography- clinical examinations of possible late complications with special regards to neurological findings (author's transl)]. / Die Pantopaquezisternographie. Langzeitnachuntersuchungen zur Frage von Nebenwirkungen unter besonderer Berücksichtigung neurologischer Gesichtspunkte.

Extensive examinations after couple of months or years after pantopaque-cisternography were performed in 20 patients, in whom no central nervous system diseases were known and in whom no surgery of CNS was previously performed. With only one exception the contrast medium was found intracranially with preference to the sella and to the region of the frontobasis. No connection was found between the amount of pantopaque and the length of time since the performance of cisternography. No late neurological complications were observed.