The 2016 revision of the WHO Classification of Central Nervous System Tumours: retrospective application to a cohort of diffuse gliomas.

The classification of central nervous system tumours has more recently been shaped by a focus on molecular pathology rather than histopathology. We re-classified 82 glial tumours according to the molecular-genetic criteria of the 2016 revision of the World Health Organization (WHO) Classification of Tumours of the Central Nervous System. Initial diagnoses and grading were based on the morphological criteria of the 2007 WHO scheme. Because of the impression of an oligodendroglial component on initial histological assessment, each tumour was tested for co-deletion of chromosomes 1p and 19q and mutations of isocitrate dehydrogenase (IDH-1 and 2) genes. Additionally, expression of proteins encoded by alpha-thalassemia X-linked mental retardation (ATRX) and TP53 genes was assessed by immunohistochemistry. We found that all but two tumours could be assigned to a specific category in the 2016 revision. The most common change in diagnosis was from oligoastrocytoma to specifically astrocytoma or oligodendroglioma. Analysis of progression free survival (PFS) for WHO grade II and III tumours showed that the objective criteria of the 2016 revision separated diffuse gliomas into three distinct molecular categories: chromosome 1p/19q co-deleted/IDH mutant, intact 1p/19q/IDH mutant and IDH wild type. No significant difference in PFS was found when comparing IDH mutant grade II and III tumours suggesting that IDH status is more informative than tumour grade. The segregation into distinct molecular sub-types that is achieved by the 2016 revision provides an objective evidence base for managing patients with grade II and III diffuse gliomas based on prognosis.

A case of conus medullaris teratoma.

In this report, we present a case of an adult patient with a mature teratoma of the conus medullaris. The patient was a 29-year-old postpartum female patient who developed unexplained urinary retention. Lumbar spine magnetic resonance imaging (MRI) examination revealed an intradural partly enhancing mixed cystic and solid lesion with intralesional intrinsic T1 hyperintense components that were suppressed on fat suppressed sequences, inseparable from the conus medullaris. Surgical resection was performed and histopathology findings were consistent with a mature teratoma. The patient made a complete recovery.

Intracranial white epidermoid cyst with dystrophic calcification - A case report and literature review.

White epidermoids are a rare variant of an intracranial epidermoid cyst that do not exhibit typical 'near- cerebrospinal fluid (CSF)' CT density or MRI intensity. Here, the authors present the case of a 58year old man with an acute onset of aphasia and altered consciousness, due to a large heterogeneous cranial mass in the left frontal region with unusual signal intensity. Subsequent histopathological analysis identified the lesion as an epidermoid cyst.

Tenosynovial giant cell tumour of brachial plexus.

Tenosynovial giant cell tumours (TGT) are benign tumours that arise in the synovial lining of joints, tendon sheaths and bursae. Tumours arising from the vertebral column are extremely rare, with few cases reported. In this article, we describe an unusual case of an extra-articular TGT of the brachial plexus, arising from the synovium of the vertebral facet joint. To our knowledge and after a review of the literature, this is the first patient with a TGT involving the brachial plexus. The clinical, radiological and histological features of this tumour are described together with a brief discussion of management options.