Optimizing the risk stratification of astrocytic tumors by applying the cIMPACT-NOW Update 3 signature: real-word single center experience.

Our work reports implementation of a useful genetic diagnosis for the clinical managment of patients with astrocytic tumors. We investigated 313 prospectively recruited diffuse astrocytic tumours by applying the cIMPACT-NOW Update 3 signature. The cIMPACT-NOW Update 3 (cIMPACT-NOW 3) markers, i.e., alterations of TERT promoter, EGFR, and/or chromosome 7 and 10, characterized 96.4% of IDHwt cases. Interestingly, it was also found in 48,5% of IDHmut cases. According to the genomic profile, four genetic subgroups could be distinguished: (1) IDwt/cIMPACT-NOW 3 (n = 270); (2) IDHwt/cIMPACT-NOW 3 negative (= 10); (3) IDHmut/cIMPACT-NOW 3 (n = 16); and 4) IDHmut/cIMPACT-NOW 3 negative (n = 17). Multivariate analysis confirmed that IDH1/2 mutations confer a favorable prognosis (IDHwt, HR 2.91 95% CI 1.39-6.06), and validated the prognostic value of the cIMPACT-NOW 3 signature (cIMPACT-NOW 3, HR 2.15 95% CI 1.15-4.03). To accurately identify relevant prognostic categories, overcoming the limitations of histopathology and immunohistochemistry, molecular-cytogenetic analyses must be fully integrated into the diagnostic work-up of astrocytic tumors.

New somatic TERT promoter variants enhance the Telomerase activity in Glioblastoma.

The catalytic activity of human Telomerase Reverse Transcriptase (TERT) compensates for the loss of telomere length, eroded during each cell cycle, to ensure a correct division of stem and germinal cells. In human tumors, ectopic TERT reactivation, most frequently due to hotspot mutations in the promoter region (TERTp), i.e. c.1-124 C > T, c.1-146 C > T, confers a proliferative advantage to neoplastic cells. In gliomas, TERTp mutations (TERTpmut) mainly occur in oligodendroglioma and glioblastoma. We screened, for TERTp hotspot mutations, 301 adult patients with gliomas and identified heterozygous mutations in 239 cases: 94% of oligodendroglioma, 85% of glioblastoma, and 37.5% of diffuse/anaplastic astrocytoma. Besides the recurrent c.1-124 C > T and c.1-146 C > T, two cases of glioblastoma harbored novel somatic TERTp variants, which consisted of a tandem duplications of 22 nucleotides, i.e. a TERTp c.1-100_1-79dup and TERTp c.1-110_1-89, both located downstream c.1-124 C > T and c.1-146 C > T. In silico analysis predicted the formation of 119 and 108 new transcription factor's recognition sites for TERTp c.1-100_1-79dup and TERTp c.1-110_1-89, respectively. TERTp duplications (TERTpdup) mainly affected the binding capacity of two transcription factors' families, i.e. the members of the E-twenty-six and the Specificity Protein/Krüppel-Like Factor groups. In fact, these new TERTpdup significantly enhanced the E-twenty-six transcription factors' binding capacity, which is also typically increased by the two c.1-124 C > T/c.1-146 C > T hotspot TERTpmut. On the other hand, they were distinguished by enhanced affinity for the Krüppel proteins. The luciferase assay confirmed that TERTpdup behaved as gain-of-function mutations causing a 2,3-2,5 fold increase of TERT transcription. The present study provides new insights into TERTp mutational spectrum occurring in central nervous system tumors, with the identification of new recurrent somatic gain-of-function mutations, occurring in 0.8% of glioblastoma IDH-wildtype.

Paraganglioma of the cauda equina region.

BACKGROUND CONTEXT: Cauda equina paragangliomas (CEPs) are rare neuroendocrine tumors. The difficulty in differential diagnosis with other tumors of this region may be misleading for surgical planning and prognostic expectations. PURPOSE: To report on a rare case of CEP and review the most current information regarding the diagnosis, treatment options, and outcomes. STUDY DESIGN: Case report and literature review. PATIENT SAMPLE: One patient affected by CEP. METHODS: We report on a 33-year-old woman with a 2-month history of worsening low back pain, aggravated by sitting, bending, and coughing. Neurological examination revealed normal power and muscular tone, no sensory or sphincter abnormality, and normal reflex. Magnetic resonance imaging of the lumbar spine demonstrated an intradural extramedullary lesion at L3, with homogeneous contrast enhancement and hypointense punctate foci. The patient underwent an L3 laminectomy and tumor removal. Relevant articles covering CEPs from 1970 to the present were reviewed. RESULTS: The histopathological examinations described paraganglioma features. The postoperative course was uneventful, and all the symptoms resolved, with no tumor recurrence after 3 years' follow-up. CONCLUSIONS: Cauda equina paragangliomas are rare, benign, and slow-growing tumors. Except for its secreting tumor characteristics, preoperative CEP diagnosis is very difficult. Magnetic resonance imaging is important and may suggest specific radiological features for these tumors; however, these are only relative, and it is rare that diagnosis is made before surgery. Diagnosis is established by histological examination and electron microscopy, and immunohistochemical techniques must be used to achieve a correct diagnosis. Cauda equina paragangliomas are well-encapsulated tumors that may be cured by surgery alone, whereas radiotherapy is reserved for incompletely resected tumors. Overall, prolonged postoperative observation is mandatory because of the slow tumor evolution and the possibility of tumor relapse even up to 30 years after surgery.

An unusual growth of an intraventricular meningioma: a case report.

Intraventricular meningiomas are rare often histologically benign tumors arising most always from the trigonal region of the lateral ventricle. We report the first described case of a rapidly growing histologically benign intraventricular meningioma in a 68-year-old woman whose magnetic resonance imaging (MRI) executed 1 year before surgical operation was negative for intracranial mass lesion.