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not appropriate in light of ethical and social norms, or if the patient is unable to consent to the test because of his or her firm beliefs, the physician may refuse the test after a thorough explanation of the reasons.・ However, if the patient refuses the test because of his/her own beliefs, referral to another medical institution should be considered.・ For hereditary diseases that develop in later adulthood, and there is no established cure or prevention. In general, genetic testing should be avoided during childhood.・ From the standpoint of protecting future free will, genetic testing of minors is not recom-mended, unless the test results indicate that immediate treatment or preventive measures should be taken or there is an emergency , it should be withheld until the individual reaches adulthood.Sporadic TumorsAmong the medical treatments currently known as genomic medicine, treatment for sporadic tumors account for two-thirds of the total3). Recent devel-opments in the field of molecular biology have increased the options for the medical treatment of developing tumors. It is known that when a tumor develops, some genetic abnormality occurs. Due to the many genomic changes that occur in cancer cells, it is not possible to truly understand cancer cell develop-ment and maintenance. Therefore, we need to iden-tify the mutations involved in their maintenance. Our efforts should focus on identifying the factors involved in maintenance.Research on this has resulted in drugs that target specific molecular biological mutations and have replaced the cytotoxic, tumor-killing, and chemotherapeutic agents of the past5). In other words, if a tumor has a specific genetic abnormality and is prone to growth and metastasis due to that genetic abnormality, then a drug that repairs that genetic abnormality alone can be administered to suppress growth and metastasis6). The development of ther-apeutic drugs in this field has attracted a great deal of attention, and in recent years, it has come to account for the majority of research papers7).The hallmark of these drugs is that they are not organ-specific. For example, molecular biological mutations associated with the ALK gene cause a variety of tumors, such as neuroblastoma, non-small cell lung cancer, lymphoma, and inflammatory myofibroblastic tumor8). These genetic abnormali-ties are being discovered every day, and it is now suggested that rather than considering tumor development by organ, it may be more directly relevant for treatment if tumors are considered on the basis of genetic abnormality9). There are many different types of genetic abnor-malities, some with increasing numbers of muta-tions, others with one copy activated on oncogene, both copies inactivated in tumor suppressor gene, activated oncogene by gene fusion via translocation, abnormal genomic amplification, and homozygous deletion, leading to both copies of gene being deleted.There are various approaches to repair genetic abnormalities, including targeting angiogenesis, targeting immunological mechanisms, and directly acting on genetic abnormalities10).This recent trend in cancer genomic medicine also applies to tumors of the central nervous system. First of all, the evaluation of genetic muta-tions has become necessary for the diagnosis of brain tumors, and the 2016 revision of the WHO diagnostic criteria for brain tumors now includes molecular biological diagnosis in addition to the previously used histopathological diagnosis11). Moreover, the molecular biological diagnoses are more prognostic. For example, the prognostic factors for high-grade glioma are age at diagnosis, residual tumor volume, pretreatment performance status, O-6-Methylguanine-DNA methyltrans-ferase (MGMT) promoter methylation, and isoci-trate dehydrogenase (IDH) mutation, which means that the only factor that can be controlled by the medical side is the residual tumor volume after surgery, which depends on the molecular biological properties of the tumor12).The development of molecular analysis and the segmentation of tumor types sometimes creates confusion in clinical practice, but they can also bring benefits. For example, gefitinib, which has been used for non-small cell lung cancer, is effec-tive in some non-small cell lung cancers with EGFR gene abnormalities. Although the tumor classifica-549Central Nervous System Tumors and Cancer Panel Testing