Risk factors for primary brain tumors in children and adults

Quinn TOstrom of the Baylor College of Comprehensive Cancer Center in Houston, Texas, USA, and others review the risk factors for primary brain tumors in children and adults, published online July 2019 in Neuro-Oncology- Excerpted from the articleRef: Ostrom QT,et al.
Neuro Oncol.2019 Jul 12pii: noz123doi: 10.1093/neuonc/noz123in the United Statesprimary brain tumors (primary brain tumors, BTs) account for about 1% of new cancer cases and 2% of cancer deathsBTs are the most common solid tumors in children, with higher morbidity and mortalitycentral nervous system (CNS) tumors include tumors originating in brain tissue, cranial nerves, spinal nerves and meningescan be divided into more than 100 types of histological stological stologically according to cell origin and histopathology characteristicsBTs contain malignant or benign tumors, who are classified as I-IVmost BTs are non-malignant (WHO I./II), with meningioma as the mainthe most common malignant tumor (WHO III./IV) is glioma, of which glioblastoma (GBM) is the most common subtype Review of Risk Factors for Primary Brain Tumors in Children and Adults, including Quinn T Ostrom of Baylor College of Medicine, Texas, USA, in the July 2019 issue of Neuro-Oncology online genetic risk factors: Since rapid whole genome mapping, 8 glioma whole genome association studies (GWAS), 2 meningioma GWAS, 1 pituitary adenoma GWAS and 2 primary central nervous system Lymphoma GWAS have been carried out The study identified 30 genomic variants associated with BTs risk, including 25 glioma variants, 2 meningioma variants and 3 pituitary adenoma variants The incidence of glioma is attributable to 25 per cent of genetic factors, of which 30 per cent can be explained by the currently determined variation and 70 per cent unexplained These factors are strongly correlated with the classification and histology of glioma Of the 25 single nucleotide polymorphisms, 11 were significantly associated with GBM and 18 were significantly associated with low-grade gliomas The strongest association identified to date is CCDC26 (rs55705857), which increases the risk of low-grade gliomas, which are closely related to less protrusion gliomas Genetic factors related to the risk of BTs outside of glioma have not been well studied There has been little and no public GWAS research on genetic correlations in childhood brain tumors (childhood brain tumors), and the effects of common genetic variants on the risk of CBTs are largely unknown, so gWAS is necessary in CBTs, and this kind of work is being done demographic factors: The incidence of BTs increased with age, especially the incidence of malignant gliomas showed twin-peak symbres, and the incidence of the disease was higher in the youth and old age populations Age distribution is related to histology types Embryonic tumors, including myeloma and primary neuroblastoma (PNET), are most common in children under 10 years of age The incidence of pituitary tumors is also a twin-peak type, with a peak in adolescence and a peak again in old age In terms of sex, the incidence of malignant tumors is high in men, while the incidence of non-malignant tumors in women is high identified and potentialnonist risk factors: The only potential risk factors associated with brain tumors are ionizing radiation and allergy history in epidemiological studies Numerous studies have shown that the history of allergic diseases can reduce the risk of glioma by 30%, and its protective effect varies according to the histology of glioma The mechanism is not clear and may be related to the allergy-enhanced immune surveillance state and inhibits abnormal cell growth of brain tumors Medium and high doses of ionizing radiation in are clear environmental risk factors for BTs Ionizing radiation is more carcinogenic to children because they are sensitive to radiation and mask the risk with a longer potential lifespan Radiation therapy for childhood cancer is associated with the subsequent occurrence of BTs, typically bTs after radiotherapy of acute lymphoblastic leukemia The incubation period of radiation therapy and BTs occurs is about 7-9 years; Diagnostic radiation during pregnancy has been found to be associated with an increased risk of BTs Excessive use of diagnostic techniques such as CT and PET can cause health-harming problems many other factors are being studied, including the relationship between aspirin and glioma, body mass index and meningioma, and the birth characteristics of CBTs Because of the low overall incidence of BTs, it is difficult to identify risk factors But based on multicenter collaborative studies, many existing studies have found that there may be more evidence in the future to further determine the role of genes and the environment in BTs Some research advances may be critical to understanding BTs risk factors in the future, such as improving risk factor detection, "OMIC" approach to species risk and tumor phenotypes, and new approaches to risk factor studies and data calculations for different populations The continuous development of large clinical databases, including pre-diagnostic risk factor data and tumor subtype molecular characteristics, resulted in more detailed BTs phenotypes.