IDH1/2 Mutations in Patients With Diffuse Gliomas: A Single Centre Retrospective Massively Parallel Sequencing Analysis.

Patients below 55 years were genetically studied because the prevalence of isocitrate dehydrogenase 1 (IDH1) decreases in older patients and on grounds of cost-effectiveness, as suggested by the World Health Organization (WHO) in 2016. The aim of our study was to use novel massively parallel sequencing (MPS) approaches to examine rare variants of IDH1/2 in Czech diffuse astrocytic and oligodendroglial tumors (gliomas) patients below 55 years of age who had been immunohistochemically (IHC) diagnosed as IDH1 R132H negative. The IHC IDH1 status (wild type or mutant) of 275 tissue samples was analyzed using antibodies against the IDH1 R132H protein. Sixty-three samples of 55 years old patients with IHC IDH1 WT status were genotyped using two different MPS technologies to detect rare IDH1 and IDH2 variants. The tiered IHC (60 positive) and molecular (10 positive) approach thus revealed that 70 of the 275 samples (25%) bore IDH1/IDH2 mutations. The combined molecular and IHC approach thus revealed that 70 of the 275 samples (25%) considered in the study bore IDH1/IDH2 mutations. IHC detection of the IDH1 R132H variant should be routinely complemented with MPS to detect rare IDH1/2 variants in glioma patients below 55 years of age with negative IHC result of IDH R132H variant.

Very late complications of oncotherapy in glioblastoma patients: A case series.

BACKGROUND: Stroke-like syndrome is defined as a rare, delayed complication of brain oncotherapy. Cases with more favorable brain cancer diagnoses and longer life expectancy have been previously reported, but here we present, for the first time, three long-term survivors of glioblastoma with stroke-like syndromes. METHODS AND RESULTS: Three young or middle-aged patients underwent tumor resection and chemoradiotherapy. They received regular clinical and imaging follow-up with stable neurological status and no signs of tumor recurrence. They exhibited varied signs and symptoms (motor and sensory deficits, aphasia, memory and cognitive disorders, seizures, and headache) accompanied by imaging abnormalities. Stroke-like syndromes developed within 2-5 days and resolved in 2-6 weeks. Diffusion-weighted MRI and T2 brain perfusion abnormalities were demonstrated in all patients. In addition, there was focal T1 MRI contrast enhancement due to blood-brain barrier disruption. In addition to tumor recurrence, classic stroke, encephalitis, metabolic and mitochondrial disorders, and post-seizure swelling should be excluded. The imaging indicated intensive MRI scanning and symptomatic medication (steroids supplemented by antiepileptics, vasoactive agents, etc.) for judicious management. With respect to the course, an invasive procedure was still considered an option. CONCLUSION: All stroke-like syndromes are diagnoses of exclusion. To avoid misinterpretation of imaging findings as glioblastoma recurrence and avert recall oncotherapy or redundant interventions, better understanding of delayed complications of brain tumor therapy is crucial.

The Influence of Gene Aberrations on Survival in Resected IDH Wildtype Glioblastoma Patients: A Single-Institution Study.

This prospective population-based study on a group of 132 resected IDH-wildtype (IDH-wt) glioblastoma (GBM) patients assesses the prognostic and predictive value of selected genetic biomarkers and clinical factors for GBM as well as the dependence of these values on the applied therapeutic modalities. The patients were treated in our hospital between June 2006 and June 2015. Clinical data and tumor samples were analyzed to determine the frequencies of TP53, MDM2, EGFR, RB1, BCR, and CCND1 gene aberrations and the duplication/deletion statuses of the 9p21.3, 1p36.3, 19q13.32, and 10p11.1 chromosome regions. Cut-off values distinguishing low (LCN) and high (HCN) copy number status for each marker were defined. Additionally, MGMT promoter methylation and IDH1/2 mutation status were investigated retrospectively. Young age, female gender, Karnofsky scores (KS) above 80, chemoradiotherapy, TP53 HCN, and CCND1 HCN were identified as positive prognostic factors, and smoking was identified as a negative prognostic factor. Cox proportional regression models of the chemoradiotherapy patient group revealed TP53 HCN and CCND1 HCN to be positive prognostic factors for both progression-free survival and overall survival. These results confirmed the influence of key clinical factors (age, KS, adjuvant oncotherapy, and smoking) on survival in GBM IDH-wt patients and demonstrated the prognostic and/or predictive importance of CCND1, MDM2, and 22q12.2 aberrations.

Genetic Markers in Triple-Negative Breast Cancer.

Triple-negative breast cancer (TNBC) accounts for 15% to 20% of breast cancer cases and is characterized by the absence of estrogen, progesterone, and human epidermal growth factor 2 receptors. Though TNBC is a highly heterogenic and aggressive disease, TNBC patients have better response to neoadjuvant therapy compared to other breast cancer subtypes. Nevertheless, patients with residual disease have a very poor prognosis, with higher probability of relapse and lower overall survival in the first years after diagnosis. TNBC has 6 subtypes with distinct molecular signatures with different prognoses and probably different responses to therapy. The precise stratification of TNBC is therefore crucial for the development of potent standardized and targeted therapies. In spite of intensive research into finding new molecular biomarkers and designing personalized therapeutic approaches, BRCA mutational status is the only clinically validated biomarker for personalized therapy in TNBC. Recent studies have reported several promising biomarkers that are currently being validated through clinical trials. The objective of this review was to summarize the clinically relevant genetic markers for TNBC that could serve as diagnostic, prognostic, or predictive or could improve personalized therapeutic strategies.