Inflammatory myofibroblastic tumor of the ulnar nerve. Case report and review of the literature

Inflammatory myofibroblastic tumors with involvement of cranial and peripheral nerves are exceedingly rare. The authors present the case of a 67-year-old man with an inflammatory myofibroblastic tumor of the left ulnar nerve, which was identified intraoperatively and mimicked a malignant neoplastic lesion. Histopathological examination revealed loosely structured fibrous tissue and collagen deposits intermingled with patchy infiltrates of lymphocytes, plasma cells, and histiocytes penetrating the endo- and epineurium of the affected nerve fascicles. There was strong expression of vimentin and actin in spindle cells throughout the lesion. The histiocytes were CD68- and major histocompatibility complex class II-positive, but lacked CD1a expression. A review of the literature revealed nine histopathologically confirmed cases of inflammatory myofibroblastic tumors involving peripheral or cranial nerves in which slight differences in histopathological features and surgical management were found, which are discussed here.

De novo erythropoietin receptor (EPO-R) expression in human neoplastic glial cells decreases with grade of malignancy but is favourably associated with patient survival

The erythropoietin receptor (EPO-R) is mainly known as a regulator of erythropoiesis. However, recent studies revealed that the EPO-R is not exclusively expressed in haematopoietic tissues but also in various cancer cell types and normal tissue such as the central nervous system (CNS). EPO-R is up-regulated under hypoxia and is able to counteract the deleterious effects of hypoxia on tumour growth, metastasis and treatment resistance. Therefore, the EPO-EPO-R signalling pathway is considered as a possible target for tumour treatment. Here, we investigated brain tumour samples obtained from patients between 1993 and 2003 to study EPO-R expression in vivo. Tissue samples included 194 gliomas of different WHO grades, additionally 25 infiltration zone samples and 31 relapses of WHO grade IV glioblastomas as well as 23 normal CNS tissue specimens to address the in vivo situation. Immunohistochemistry of the tissue microarray samples revealed significantly higher levels of EPO-R expression in neoplastic glial cells compared with glial cells derived from normal brain. EPO-R expression showed a highly significant decrease from low- to high-grade gliomas. Age-stratified Kaplan-Meier analysis revealed longer survival for patients exhibiting high EPO-R status in high-grade gliomas. Our results show a grade-dependent EPO-R down-regulation and might contribute to the understanding of high-grade glioma resistance to radio- and chemotherapy as both were shown to be improved by a well functioning EPO-EPO-R pathway in previous studies. Further studies are needed to investigate to what extent the decreased mortality in age-stratified patient groups with high EPO-R levels reflects a direct beneficial role of EPO-R expression.

Malignant glioma cells counteract antitumor immune responses through expression of lectin-like transcript-1

Glioblastoma, one of the most lethal tumors, is paradigmatic for tumor-associated immunosuppression. Lectin-like transcript-1 (LLT1) is a newly identified ligand for the inhibitory natural killer (NK) cell receptor CD161. Here, we report that glioma cells express LLT1 mRNA and protein in vitro and in vivo, whereas expression levels in normal brain are low. LLT1 expression in human gliomas increases with the WHO grade of malignancy. We further show that transforming growth factor-beta (TGF-beta) up-regulates the expression of LLT1 in glioma cells. Small interfering RNA (siRNA)-mediated down-regulation of LLT1 in LNT-229 and LN-428 cells promotes their lysis by NK cells. Thus, LLT1 acts as a mediator of immune escape and contributes to the immunosuppressive properties of glioma cells.

Differential Expression of Egr1 and Activation of Microglia Following Irradiation in the Rat Brain

BACKGROUND

Little is known about the immediate effects of whole-brain gamma-irradiation. The authors hypothesize that Egr1 as an immediate early gene and microglia both participate in early reactions.

MATERIAL AND METHODS

Both, expression of Egr1 and cellular distribution were studied in a temporal sequence in different brain regions of rats subjected to irradiation with 10 Gy. Brain tissue was examined using immunohistochemistry, real-time RT-PCR (reverse transcription-polymerase chain reaction), and Western blotting.

RESULTS

Astroglia and oligodendroglia showed increased Egr1 immunoreactivity within the first hours following irradiation. This was accompanied by a strong peak in CD68 immunoreactivity histologically attributable to activated microglia. A high constitutive expression of Egr1 protein in the nuclei of activated neurons was reduced following irradiation and RT-PCR demonstrated significantly reduced levels of egr1-lv as a neuronal activity-related mRNA variant.

CONCLUSION

The induction of Egr1 in glial cells, as well as the activation of microglia take place earlier than histological changes reported so far. The authors revealed a temporal sequence of reactions that point toward the initiation of an immediate inflammatory response including reduced neuronal activity.

Gliosarcoma with chondroid and osseous differentiation

We present the case of a 65-year-old woman with a short-term history of cognitive decline and neuropsychiatric symptoms. Neuroradiological examinations revealed a large left temporo-occipital cystic and calcified tumor mass measuring 6 cm in diameter, which was suspicious for an oligodendroglioma or a choroid plexus carcinoma. Neuropathological investigations finally revealed a gliosarcoma with extensive mesenchymal differentiation. The tumor demonstrated a biphasic pattern consisting of focal anaplastic glial components with vascular proliferation and necrosis. Adjacent sarcomatous tissue displayed pleomorphic fibroblastic cells surrounding metaplastic cartilage and osseous formation. Accounting for only approximately 2% of glioblastomas, gliosarcomas represent a rare entity of intrinsic CNS neoplasms. Exceedingly rare, the mesenchymal part of the gliosarcoma undergoes metaplastic transformation. Interestingly, in our case, the tumor exhibited features of both cartilaginous and osseous differentiation and multifocally showed a sharp transformation zone between highly malignant gliosarcomatous tumor areas and well-differentiated non-proliferative metaplastic regions.

Expression of EAAT1 reflects a possible neuroprotective function of reactive astrocytes and activated microglia following human traumatic brain injury

Glutamate-mediated excitotoxicity is known to cause secondary brain damage following stroke and traumatic brain injury (TBI). However, clinical trials using NMDA antagonists failed. Thus, glial excitatory amino acid transporters (EAATs) might be a promising target for therapeutic intervention.

METHODS AND RESULTS

We examined expression of EAAT1 (GLAST) and EAAT2 (Glt-1) in 36 TBI cases by immunohistochemistry. Cortical expression of both EAATs decreased rapidly and widespread throughout the brain (in lesional, adjacent and remote areas) following TBI. In the white matter numbers of EAAT1+ parenchymal cells increased 39-fold within 24h (p<0.001) and remained markedly elevated till later stages in the lesion (90-fold, p<0.01) and in peri-lesional regions (86-fold, p<0.01). In contrast, EAAT2+ parenchymal cells and EAAT1+ or EAAT2+ perivascular cells did not increase significantly. Within the first days following TBI mainly activated microglia and thereafter mainly reactive astrocytes expressed EAAT1. Perivascular monocytes and foamy macrophages lacked EAAT1 immunoreactivity. We conclude that following TBI i) loss of cortical EAATs contributes to secondary brain damage, ii) glial EAAT1 expression reflects a potential neuroprotective function of microglia and astrocytes, iii) microglial EAAT1 expression is restricted to an early stage of activation, iv) blood-derived monocytes do not express EAAT1 and v) pharmacological modification of glial EAAT expression might further limit neuronal damage.

Extradural ependymal tumor with myxopapillary and ependymoblastic differentiation in a case of Schinzel-Giedion syndrome

Primary extradural ependymomas are rare neoplasms usually of the myxopapillary type. Reports on malignant primary extradural ependymal tumors are exceptionally rare. We here report on a 3-year-old boy with Schinzel-Giedion syndrome (SGS), who presented with lumbar spina bifida occulta and a progressive extraspinal lesion in the subcutaneous sacrococcygeal region. Microscopic examinations revealed an uncommon ependymal tumor with well-differentiated regions reflecting myxopapillary ependymoma and highly anaplastic regions with numerous mitoses, necroses, ependymal rosettes and ependymoblastic rosettes. Final neuropathologic diagnosis was an extraspinal anaplastic ependymal tumor with myxopapillary and ependymoblastic differentiation, corresponding to WHO grade IV. SGS is a very rare disorder with a likely autosomal recessive pattern of inheritance. So far, 42 cases have been reported, among them 7 were diagnosed to have malignant neoplasms, including three malignant sacrococcygeal teratomas, two sacrococcygeal primitive neuroectodermal tumors (PNET), one hepatoblastoma and one malignant kidney tumor. The present case is the first report on an ependymal tumor with a mixture of myxopapillary, anaplastic and ependymoblastic features and the first report on an ependymal tumor arising on the genetic background of SGS.

Expression pattern of the water channel aquaporin-4 in human gliomas is associated with blood–brain barrier disturbance but not with patient survival

Aquaporin-4 (AQP4), the most prominent CNS water channel, is restricted to the glia limitans and astrocytic endfeet. We previously showed the loss of spatial AQP4 expression in glioblastomas and a redistribution across the cell surface. However, opposing AQP4 functions have been described: protective in vasogenic but detrimental in cytotoxic brain edema. Thus, specific AQP4 induction to prevent or reduce vasogenic edema is suggested. To elucidate the AQP4 role in brain tumors, we investigated 189 WHO grade I-IV gliomas by immunohistochemistry and the prognostic significance for patients' survival. In gliomas, a remarkable de novo AQP4 redistribution was observed in comparison with normal CNS tissue. Surprisingly, the highest membraneous staining levels were seen in pilocytic astrocytomas WHO grade I and grade IV glioblastomas, both significantly higher than in WHO grade II astrocytomas. AQP4 up-regulation was associated with brain edema formation; however, no association between survival and WHO grade-dependent AQP4 expression was seen. Hence, AQP4 redistribution may go along with other tumor properties, such as vascular proliferation and resulting blood-brain barrier disturbance, features usually prominent in pilocytic astrocytomas WHO I and glioblastomas WHO grade IV. In summary, our findings question the protective role of AQP4 in vasogenic brain edema. Although AQP4 was associated with brain edema formation, one has to question the suitability of AQP4 induction as a promising approach in vasogenic brain edema prevention and treatment. In addition, our results provide unexpectedly high AQP4 levels in pilocytic astrocytomas and present AQP4 as tumor progression marker in WHO grade II-IV astrocytomas.

Upregulation of frizzled 9 in astrocytomas

Wnt/frizzled (FZD) cascades play important roles in controlling cell fate, proliferation, migration, tissue architecture and organogenesis during embryonic development and in adult organisms. The potential involvement of this pathway in tumorigenesis has been established in several types of cancers. Frizzled 9 (FZD9) is expressed in brain and its aberrant expression in gastric cancer was observed. However, its association with astrocytomas remains unknown therefore we studied FZD9 expression in astrocytomas of different malignancy. In the present study, FZD9 expression in 25 astrocytomas was investigated using immunohistochemistry with specific antibodies. Further FZD9 expression in native human brain tissue and glioblastoma cell line were analysed using real-time reverse transcription polymerase chain reaction (RT-PCR). In human astrocytomas, FZD9 immunoreactivity (IR) was observed in both microvessels and neoplastic cells. The percentage of FZD9+ microvessels in relation to FZD9+ vessels was significantly higher in malignant astrocytomas than in low-grade astrocytomas and positively correlated with the astrocytoma World Health Organization (WHO) grading (r = 1, P = 0.04). Furthermore, the FZD9 IR scores positively correlated with astrocytoma WHO grading (r = 1, P = 0.04) and proliferating activity (r = 0.77, P < 0.001). Real-time RT-PCR data showed that FZD9 expression in human glioblastoma was significant higher than in normal brain (P < 0.05) but FZD9 expression was only slightly induced in cobalt chloride-treated human glioblastoma T98G cells compared with untreated cells (P > 0.05). FZD9 is upregulated in astrocytomas, suggesting that FZD9 could be important in the tumorigenesis of human astrocytomas.

Differential microglial regulation in the human spinal cord under normal and pathological conditions

As the primary intrinsic immune effector cells of the central nervous system, microglia are involved in virtually all pathological processes of the brain and spinal cord including inflammatory, neurodegenerative, traumatic, neoplastic and vascular diseases. Despite this important role, there is a lack of data concerning microglial distribution and protein expression in the human spinal cord. In this study, we immunohistochemically investigated 10 normal human spinal cords to establish reference data and compared these results with 15 pathological human spinal cords deriving from distinct pathologies. Each spinal cord was evaluated at eight different levels for three white and two grey matter areas for both constitutive (MHC-II, CD68, IL-16, AIF-1, LCA, CD4) and reactive (MRP-8, MRP-14) microglial antigens. Whereas previous studies revealed significant regional differences in microglial distribution and protein expression in human brain, normal spinal cord displayed a uniform expression pattern, reaching levels of up to 17% MHC-II positive cells of the total cell population. This datum formed the basis for the further evaluation of microglia expression levels in pathological spinal cords, where levels of up to 45% positive cells were observed. Our results represent important reference values for future neuropathological diagnostic and therapeutical approaches in spinal cord pathologies.

Albumin in Immunohistochemistry: Foe and Friend

Immunohistochemical procedures constitute a high methodological value in both pathologic diagnostics and research. Staining quality depends on a large variety of interference factors. Primarily, background staining reduces the quality of evaluation by reducing the chromatic discrimination. For the identification of important interference factors, various incubation steps and composition of solutions recommended in routine protocols were altered or omitted in our study. Surprisingly, the most important effect concerning background staining reduction could be significantly attributed to the omission of albumin which usually is recommended as a reducer of background stainings. However, in contrast to this negative effect, albumin could also increase specific staining intensity. These findings lead to the recommendation of a careful use of albumin in immunohistochemistry because of the dichotomous effects mentioned above. Furthermore, these results imply that in case of a good specific staining pattern, the use of albumin in immunohistochemical solutions merely exerts significant negative background staining effects.

Multiple thromboembolic events in fetofetal transfusion syndrome in triplets contributing to the understanding of pathogenesis of hydranencephaly in combination with polymicrogyria

Over the last 180 years, several theories concerning the origin of hydranencephaly have been proposed with an emphasis on infectious, aplastic, and vascular etiologies. In this report, we present a case of triplets with fetofetal transfusion syndrome of which 2 fetuses (1 and 2) developed almost similar hydranencephaly, whereas the third exhibited the features of a fetus papyraceus (3). In the monochorial triamniotic placenta, multiple arteriovenous anastomoses were detected, representing a probable route for the transmission of thrombi originating from fetus 3 causing visceral lesions in fetus 2. Hydranencephaly was histologically characterized by necrosis, macrophage invasion, and endothelial proliferation. In addition, polymicrogyria was seen in fetuses 1 and 2. The combination of multiple visceral thromboembolic events and the death of fetus 3 approximately in the 11th week of gestation suggested a vascular thrombotic pathogenesis of hydranencephaly. Polymicrogyria can be considered as postmigratory laminar necrosis. Our findings contribute to the pathogenetic understanding of combined hydranencephaly and polymicrogyria.

Phase II trial of lomustine plus temozolomide chemotherapy in addition to radiotherapy in newly diagnosed glioblastoma: UKT-03

PURPOSE

To evaluate toxicity and efficacy of the combination of lomustine, temozolomide (TMZ) and involved-field radiotherapy in patients with newly diagnosed glioblastoma (GBM).

PATIENTS AND METHODS

Thirty-one adult patients (median Karnofsky performance score 90; median age, 51 years) accrued in two centers received involved-field radiotherapy (60 Gy in 2-Gy fractions) and chemotherapy with lomustine 100 mg/m2 (day 1) and TMZ 100 mg/m2/d (days 2 to 6) with individual dose adjustments according to hematologic toxicity.

RESULTS

A median of five courses (range, one to six courses) were delivered. WHO grade 4 hematotoxicity was observed in five patients (16%) and one of these patients died as a result of septicemia. Nonhematologic toxicity included one patient with WHO grade 4 drug-induced hepatitis (leading to discontinuation of lomustine and TMZ) and one patient with WHO grade 2 lung fibrosis (leading to discontinuation of lomustine). The progression-free survival (PFS) rate at 6 months was 61.3%. The median PFS was 9 months (95% CI, 5.3 to 11.7 months), the median overall survival time (MST) was 22.6 months (95% CI, 12.5 to not assessable), the 2-year survival rate was 44.7%. O6-methylguanine-DNA methyltransferase (MGMT) gene-promoter methylation in the tumor tissue was associated with longer PFS (P = .014, log-rank test) and MST (P = .037).

CONCLUSION

The combination of lomustine, TMZ, and radiotherapy had acceptable toxicity and yielded promising survival data in patients with newly diagnosed GBM. MGMT gene-promoter methylation was a strong predictor of survival.

TGF-beta and metalloproteinases differentially suppress NKG2D ligand surface expression on malignant glioma cells

NKG2D ligands (NKG2DL) are expressed by infected and transformed cells. They transmit danger signals to NKG2D-expressing immune cells, leading to lysis of NKG2DL-expressing cells. We here report that the NKG2DL MHC class I-chain-related molecules A and B (MICA/B) and UL16-binding proteins (ULBP) 1-3 are expressed in human brain tumours in vivo, while expression levels are low or undetectable in normal brain. MICA and ULBP2 expression decrease with increasing WHO grade of malignancy, while MICB and ULBP1 are expressed independently of tumour grade. We further delineate two independent mechanisms that can explain these expression patterns: (i) transforming growth factor-beta (TGF-beta) is upregulated during malignant progression and selectively downregulates MICA, ULBP2 and ULBP4 expression, while MICB, ULBP1 and ULBP3 are unaffected. (ii) Cleavage of MICA and ULBP2 is reduced by inhibition of metalloproteinases (MP), whereas no changes in the expression levels of other NKG2DL were detected. Consequently, NKG2DL-dependent NK cell-mediated lysis is enhanced by depletion of TGF-beta or inhibition of MP. Thus, escape from NKG2D-mediated immune surveillance of malignant gliomas in vivo may be promoted by the inhibition of MICA and ULBP2 expression via an autocrine TGF-beta loop and by MP-dependent shedding from the cell surface. Loss of MICA and ULBP2, in contrast to other NKG2DL, may be particularly important in glioma immune escape, and differential regulation of human NKG2DL expression is part of the immunosuppressive properties of human malignant glioma cells.

Endostatin/Collagen XVIII Accumulates in Patients with Traumatic Brain Injury

In patients with traumatic brain injury (TBI), hypoperfusion contributes to ongoing and expanding areas of neuronal damage long after the initial trauma has ceased. In order to evaluate whether the antiangiogenic protein endostatin may play a role in this process, we analyzed its spatial distribution in brains of 18 patients with TBI. We observed an increase of endostatin/collagen XVIII(+) macrophages/microglial cells but not astrocytes up to day 14 and a consequent decrease to day 16 post-TBI. In addition, paracellular endostatin/collagen XVIII deposits were detected. In vitro experiments revealed that microglial endostatin release is induced predominantly by hypoxia and, to a lesser extent, by reactive oxygen intermediates. Common NO synthase inhibitor pharmacotherapy with aminoguanidine and L-NAME completely abolished endostatin release from microglial cells, raising hopes of altering endostatin release in vivo.

Choroid plexus tumors differ from metastatic carcinomas by expression of the excitatory amino acid transporter-1

Tumors of the choroid plexus (CPTs) are rare neoplasms of neuroectodermal origin usually arising in pediatric patients. However, CPT may occur at any age, and their distinction from metastatic carcinomas is often difficult in adult cases. Because CPTs frequently show focal glial differentiation, we now investigated 35 CPTs (19 males and 16 females 0.3-70 years old; median age, 25.0 years), including 21 choroid plexus papillomas (CPPs), 5 atypical CPP, and 9 choroid plexus carcinomas regarding their expression of the excitatory amino acid transporter-1 (EAAT1, corresponding to rodent GLAST/GLAST-1) by immunohistochemistry. In addition, 77 metastatic carcinomas, including 64 adenocarcinomas with mostly papillary formations, derived from different organs were examined. Of the 35 CPTs, 23 (66%) showed membranous EAAT1 expression in variable numbers of tumor cells, including all atypical CPP and 3 of 9 choroid plexus carcinomas (33%). None of the metastatic carcinomas showed membranous immunostaining. Excitatory amino acid transporter-1 expression in CPT was significantly age dependent (P < .0001), with the proportion of EAAT1-positive tumor cells increasing with age, but not sex dependent. There was a highly significant difference between EAAT1 expression in CPT and in metastatic carcinomas (P < .0001). Establishing a cutoff value of 1% immunoreactive tumor cells served in adult cases to distinguish CPT from metastatic adenocarcinomas with 100% specificity and 70% sensitivity and was associated with positive and negative predictive values of 100% and 91%, respectively. Our findings indicate that EAAT1 immunohistochemistry may be useful in differentiating CPT from metastatic carcinomas.

Coincidence of semilobar holoprosencephaly and Chiari II malformation: correlation of prenatal diagnostics and neuropathologic findings

As holoprosencephaly and Chiari II malformation differ considerably, both in pathogenesis and in phenotypic localization, the coincidence of both entities is extremely rare. The case presented is, to our knowledge, the first published report comprising a combination of a semilobar holoprosencephaly associated with a Chiari II malformation and a myelomeningocele diagnosed prenatally and confirmed by postmortem neuropathologic evaluation. These findings indicate that in the case of pre- and postnatal detection of a myelomeningocele and/or Chiari II malformation, possible additional intracranial malformation, such as a semilobar holoprosencephaly, should also be taken into account and vice versa.

Bag-1 and Bcl-2 gene transfer in malignant glioma: modulation of cell cycle regulation and apoptosis

Bag-1 is a heat shock 70 kDa (Hsp70)-binding protein that can collaborate with Bcl-2 in suppressing apoptosis under some conditions. Here, we report that 11 of 12 human glioma cell lines express Bag-1 protein in vitro. Moreover, 15 of 19 human glioblastomas expressed Bag-1 as assessed by immunohistochemistry in primary tumor specimens. To examine the biological effects of Bag-1 in glioma cells, we expressed Bag-1 or Bcl-2 transgenes in 2 human malignant glioma cell lines, LN-18 and LN-229. Bag-1 significantly slowed glioma cell growth and reduced clonogenicity of both cell lines in vitro. Coexpressed Bcl-2 abrogated these effects of Bag-1. Intracranial LN-229 glioma xenografts implanted into nude mice revealed a substantial growth advantage afforded by Bcl-2. Bag-1 had no such effect, either in the absence or presence of Bcl-2. Upon serum starvation in vitro, Bcl-2 prevented cell death whereas Bag-1 did not. Both Bcl-2 and Bag-1 slowed proliferation of serum-starved cells when expressed alone. Importantly, coexpression of Bcl-2 and Bag-1 provided a distinct growth advantage under conditions of serum starvation that is probably the result of (i) the death-preventing activity of Bcl-2 and (ii) the property of Bag-1 to overcome a Bcl-2-mediated enhancement of exit from the cell cycle. In contrast to these Bcl-2/Bag-1 interactions observed under serum starvation conditions, Bag-1 did not further enhance the strong protection from staurosporine-, CD95 (Fas/Apo1) ligand-, Apo2 ligand (TRAIL)- or chemotherapeutic drug-induced apoptosis afforded by Bcl-2. Taken together, these results indicate a role for Bag-1/Bcl-2 interactions in providing a survival advantage to cancer cells in a deprived microenvironment that may be characteristic of ischemic/hypoxic tumors such as human glioblastoma multiforme, and suggest that Bcl-2/Bag-1 interactions also modulate cell proliferation.

Regeneration and Tolerance Factor: A Novel Mediator of Glioblastoma-Associated Immunosuppression

Regeneration and tolerance factor (RTF) was originally identified in placenta where it is thought to be essential for fetal allograft survival. Here we report that RTF mRNA and protein are also expressed in human glioma cells in vitro and in vivo. Suppression of RTF expression by RNA interference promotes the lysis of glioma cells by natural killer (NK) and T cells in vitro. Moreover, RTF-depleted glioma cells are less tumorigenic than control cells in nude mice in vivo. Depletion of NK cells in these animals abolished this effect. RTF is thus a novel aberrantly expressed molecule which confers immune privilege to human malignant gliomas.

Atypical pituitary adenoma exhibiting densely secretory granules and basophilia without hormone production

Herein, we report the case of a 46-year-old male patient with only one month of double vision. Radiological examination revealed a pituitary tumor. Endocrinological investigations showed no pathological alterations of anterior pituitary function. Neuropathological examinations revealed a pituitary gland adenoma with an elevated proliferation rate (MIB-1 index 4-5 %) as well as an elevated p53 expression leading to the diagnosis of an atypical pituitary adenoma. Interestingly, the tumor exhibited strong basophilia in routine histology and densely secretory granules in electron microscopy (EM). However, no hormone excess was detectable in immunohistochemistry. In contrast to clinical and immunohistochemical observations, EM and routine histology findings implied a hormone production. This discrepancy might be due to a production of unfunctional pre-stages of pituitary gland proteins in this fast growing neoplasm.

ACTH- and prolactin-producing pituitary gland microadenoma with biphasic features of atypia and intermediate filament expression

Herein, we report the case of a 28-year old woman clinically presenting with unclear weight gain over the last years. The patient displayed facial and neck edema in combination with unobtrusive striae distensae. Endocrinological examinations led to the diagnosis of Cushing's disease. Neuroradiological examination revealed an intrasellar tumor mass of 7 mm in diameter. Subsequently, transsphenoidal tumor resection was performed. Histological and immunohistochemical investigations revealed a pituitary gland adenoma showing a biphasic tumor growth pattern with two morphologically different tumor areas producing ACTH and prolactin respectively. Co-expression of ACTH and prolactin is exceedingly rare in pituitary adenoma. To our surprise, both tumor areas exhibited features of atypia consisting in elevated MIB-1 proliferation index in the ACTH-producing portion as well as p53 expression selectively in the prolactin-producing tumor parts. To our knowledge, this is the first case of an ACTH- and prolactin-producing pituitary gland adenoma exhibiting biphasic features of atypia.

Surviving glioblastoma for more than 5 years: The patient's perspective

The authors performed a comprehensive analysis of the functional outcome of 10 patients who had survived 5 years from a diagnosis of glioblastoma. Neurologic deficits were mild in most patients, but neuropsychological testing demonstrated cognitive deficits in all patients. Depression and anxiety were common. Although most patients thought that their social functioning and work ability were impaired, little reduction in overall quality of life was perceived.

Atypical teratoid-rhabdoid tumor spreading along the trigeminal nerve

We here describe the case of a boy with an atypical teratoid-rhabdoid tumor (ATRT) of the 4th ventricle at 1 year of age and a local tumor recurrence at 19 months of age. Due to brainstem infiltration, only incomplete tumor resection was possible each time. High-dose chemotherapy, stem cell transplantation and irradiation resulted in complete tumor remission on a control MRI. At 8 years of age, another tumor appeared extending from the cerebellopontine angle along the right trigeminal nerve through Meckel's cave into the cavernous sinus. The trigeminal tumor was not in continuity with the primary ATRT but was located within the field of prior irradiation, neuroradiologically mimicking a schwannoma or a meningioma. The origin of the trigeminal tumor as a late metastasis of the former ATRT or as a less likely irradiation-induced secondary ATRT and the operative approach are discussed.

Central nervous system injury-induced repulsive guidance molecule expression in the adult human brain

BACKGROUND

The repulsive guidance molecule (RGM) is involved in formation of the central nervous system during development by moderating the repulsion of growing axons. However, the role of RGM in adult central nervous system lesions remains to be clarified.

OBJECTIVE

To identify and determine RGM expression in adult brains with focal cerebral ischemia or traumatic brain injury and in neuropathologically unaffected control brains. Patients Twenty-one brains of patients with focal cerebral ischemia, 25 brains after traumatic brain injury, and 4 control brains. Main Outcome Measure Expression of RGM as assessed by immunohistochemical analysis.

RESULTS

In normal brains, RGM expression was detected on the perikarya of some neurons, choroid plexus, smooth muscle and endothelial cells, oligodendrocytes, and myelinated white matter fibers. After focal cerebral ischemia and traumatic brain injury, RGM-immunopositive cells accumulated in lesional and perilesional areas. In hemorrhagic lesions, a massive accumulation of RGM-immunopositive cells was observed. During the first week after insult, RGM expression remained confined to neurons, smooth muscle and endothelial cells, and leukocytes infiltrating the lesion. Thereafter, with maturation of the lesion, we observed RGM expression by components of the developing scar tissue, such as fibroblastoid cells, reactive astrocytes, and a pronounced extracellular RGM deposition resembling neo-laminae.

CONCLUSIONS

This is the first study of RGM in the human central nervous system. Following central nervous system injury, RGM, a novel, potent axonal growth inhibitor, is present in axonal growth impediments: the mature myelin, choroid plexus, and components of the developing scar.