A broad spectrum of posterior reversible encephalopathy syndrome - a case series with clinical and paraclinical characterisation, and histopathological findings.

Background: Posterior reversible encephalopathy syndrome (PRES) is clinical-neuroradiologically defined and potentially reversible, so there are limited data about histopathological findings. We aimed to describe the clinical and paraclinical features of patients with PRES with regard to its reversibility.

Methods: This retrospective case series encompasses 15 PRES cases out of 1300 evaluated patients from a single German center between January 1, 2010, and June 15, 2020.

Comparison between optical coherence tomography imaging and histological sections of peripheral nerves.

Objective: Optical coherence tomography (OCT) is an imaging technique that uses the light-backscattering properties of different tissue types to generate an image. In an earlier feasibility study the authors showed that it can be applied to visualize human peripheral nerves. As a follow-up, this paper focuses on the interpretation of the images obtained.

Never Too Old? Occurrence of Medulloblastoma in the Elderly beyond the 70th Year of Life.

The occurrence of medulloblastoma (MB) in the elderly is an absolutely rare event. Concerning this issue we report on two MB patients beyond the 70th year of life. Two patients older than 70 years presented with a mass in the posterior fossa without evidence of a preexisting malignant tumor.

Integrated Genomic Classification of Melanocytic Tumors of the Central Nervous System Using Mutation Analysis, Copy Number Alterations, and DNA Methylation Profiling.

In the central nervous system, distinguishing primary leptomeningeal melanocytic tumors from melanoma metastases and predicting their biological behavior solely using histopathologic criteria may be challenging. We aimed to assess the diagnostic and prognostic value of integrated molecular analysis. Targeted next-generation sequencing, array-based genome-wide methylation analysis, and BAP1 IHC were performed on the largest cohort of central nervous system melanocytic tumors analyzed to date, including 47 primary tumors of the central nervous system, 16 uveal melanomas, 13 cutaneous melanoma metastases, and 2 blue nevus-like melanomas.

Intraventricular melanocytoma diagnosis confirmed by gene mutation profile.

Primary leptomeningeal melanocytic tumors (PLMTs) are rare. They usually arise along the spinal cord and at the skull base. Here we report on a patient with a very rare intraventricular melanocytoma.

Frequent GNAQ, GNA11, and EIF1AX Mutations in Iris Melanoma.

Purpose: The most common malignant intraocular tumors with a high mortality in adults are uveal melanomas. Uveal melanomas arise most frequently in the choroid or ciliary body (97%) and rarely in the iris (3%). Whereas conjunctival and posterior uveal (ciliary body and choroidal) melanomas have been studied in more detail genetically, little data exist regarding iris melanomas.

SF3B1 and BAP1 mutations in blue nevus-like melanoma.

Blue nevi are melanocytic tumors originating in the cutaneous dermis. Malignant tumors may arise in association with or resembling blue nevi, so called 'blue nevus-like melanoma', which can metastasize and result in patient death. Identifying which tumors will behave in a clinically aggressive manner can be challenging.

Trigemino-autonomic headache and Horner syndrome as a first sign of granulomatous hypophysitis.

Objective: To report a rare case of incipient granulomatous hypophysitis presenting by atypical trigemino-autonomic cephalalgia (TAC) and Horner syndrome.

Methods: The patient was investigated with repeated brain MRI, CSF examination, thoracic CT, Doppler and duplex ultrasound of the cerebral arteries, and extensive serologic screening for endocrine and autoimmune markers. Written informed consent was obtained from the patient for access to clinical files for research purposes and for publication.

Activating cysteinyl leukotriene receptor 2 (CYSLTR2) mutations in blue nevi.

Blue nevi are common melanocytic tumors arising in the dermal layer of the skin. Similar to uveal melanomas, blue nevi frequently harbor GNAQ and GNA11 mutations. Recently, recurrent CYSLTR2 and PLCB4 mutations were identified in uveal melanomas not harboring GNAQ or GNA11 mutations.

Comparing the Prognostic Value of BAP1 Mutation Pattern, Chromosome 3 Status, and BAP1 Immunohistochemistry in Uveal Melanoma.

Uveal melanoma (UM), a tumor of the eye, can be divided into 2 major classes correlating with patients' prognosis. Gene expression profiles and chromosome 3 status are correlated with tumor classification and prognosis. Somatic BAP1 mutations are another feature largely restricted to metastatic UM.

Immunocytochemical analysis of glucose transporter protein-1 (GLUT-1) in typical, brain invasive, atypical and anaplastic meningioma.

Glucose transporter-1 (GLUT-1) is one of the major isoforms of the family of glucose transporter proteins that facilitates the import of glucose in human cells to fuel anaerobic metabolism. The present study was meant to determine the extent of the anaerobic/hypoxic state of the intratumoral microenvironment by staining for GLUT-1 in intracranial non-embolized typical (WHO grade I; n = 40), brain invasive and atypical (each WHO grade II; n = 38) and anaplastic meningiomas (WHO grade III, n = 6). In addition, GLUT-1 staining levels were compared with the various histological criteria used for diagnosing WHO grade II and III meningiomas, namely, brain invasion, increased mitotic activity and atypical cytoarchitectural change, defined by the presence of at least three out of hypercellularity, sheet-like growth, prominent nucleoli, small cell change and "spontaneous" necrosis.

Completely extradural intraspinal arteriovenous malformation in the lumbar spine: a case report.

Introduction: Spinal vascular malformations can be classified in arteriovenous malformations, cavernomas, and capillary telangiectasias. Arteriovenous malformations are the most common spinal vascular anomaly and may be located intra- and/or perimedullary. According to their nidus type and hemodynamic flow patterns, they can be differentiated into fistulous, glomerular and juvenile categories.

Methylation analysis of SST and SSTR4 promoters in the neocortex of Alzheimer's disease patients.

Several observations have pointed to a major pathogenic role of somatostatin depletion with respect to amyloid accumulation, which is often thought to be the crucial event in a cascade leading to Alzheimer's disease (AD). As methylation of CpG islands plays an important role in gene silencing, we studied the methylation status of the CpG islands in the promoters of somatostatin (SST) and in that of its receptor subtype in the cerebral cortex, SSTR4, in tissue samples from the middle temporal (Brodmann area 22) and superior frontal gyrus (Brodmann area 9) of 5 severely affected AD patients aged 72-94 years (Braak stages V-C or VI-C) and 5 non-demented controls aged 50-92 years. Bisulfite sequencing of DNA from cortical gray and infracortical white matter showed that the DNA methylation status at the promoters of SST and SSTR4 did not significantly differ between AD and control samples in any of the regions analyzed.

A 68-year old man with a cerebellopontine angle tumor.

We report on a 68-year-old male with a cerebellopontine angle tumor manifesting at the 8th cranial nerve and presenting histopathological features of a rhabdomyoma. A literature review revealed four reports of intracranial nerve rhabdomyoma, all of adult type and including one manifestation at the vestibular nerve. We present the first case of a fetal type extracardiac rhabdomyoma manifesting at a cranial nerve.

Genetic and clinico-pathologic analysis of metastatic uveal melanoma.

Uveal melanoma is the most common malignant tumor of the adult eye. Fifty percent of tumors will eventually metastasize, and there are no effective treatments for them. Recent studies of uveal melanoma have identified activating mutations in GNAQ and GNA11, loss-of-function mutations in the tumor suppressor gene BAP1, and recurrent mutations in codon 625 of SF3B1.

Exome sequencing identifies recurrent somatic mutations in EIF1AX and SF3B1 in uveal melanoma with disomy 3.

Gene expression profiles and chromosome 3 copy number divide uveal melanomas into two distinct classes correlating with prognosis. Using exome sequencing, we identified recurrent somatic mutations in EIF1AX and SF3B1, specifically occurring in uveal melanomas with disomy 3, which rarely metastasize. Targeted resequencing showed that 24 of 31 tumors with disomy 3 (77%) had mutations in either EIF1AX (15; 48%) or SF3B1 (9; 29%).

A 32-year-old male with brainstem lesions.

Schwannosis is a condition characterized by a benign proliferation of Schwann cells and an incomplete myelination of central nervous system axons following different chronic stimuli. It. has been mainly observed in the spinal cord.

Proliferation activity is significantly elevated in partially embolized cerebral arteriovenous malformations.

Background: The natural history of cerebral arteriovenous malformations (AVMs) is yet to be determined. It has been shown that angiogenic factors are involved in the pathogenesis of AVMs, in particular in partially embolized lesions. This study was conducted to investigate the expression of angiogenic and proliferative factors in relation to different clinical conditions and treatment modalities.

MET overexpressing chordomas frequently exhibit polysomy of chromosome 7 but no MET activation through sarcoma-specific gene fusions.

Overexpression of MET and polysomy 7 was formerly demonstrated in chordomas. We investigated mesenchymal-epithelial transition factor (MET) protein expression and copy numbers of chromosome 7 in human chordomas. Furthermore, tumors were screened for gene fusions (PAX3-FKHR, ASPL-TFE3, and SYT-SSX) previously shown to be associated with MET activation in sarcomas.