講演情報
[P30-5]glioblastomaを合併したBRCA2遺伝子変異によるFanconi貧血と診断された児に対する遺伝カウンセリング
○福田 憲太郎1, 増田 早織2, 松井 基浩2, 伊藤 志帆3, 黒田 真帆1, 二川 弘司1, 村松 秀樹4, 若松 学4, 吉橋 博史1 (1.東京都立小児総合医療センター 臨床遺伝科, 2.東京都立小児総合医療センター 血液・腫瘍科, 3.東京都立小児総合医療センター 看護部, 4.名古屋大学医学部附属病院 小児科)
Fanconi anemia (FA) is an inherited chromosomal instability disorder characterised by congenital and developmental abnormalities and a strong cancer predisposition. FA can be partly caused by mutations in the BRCA2 (FANCD1) gene (FA-D1) has a high risk of carcinogenesis and an extremely poor prognosis, and is inherited in an autosomal recessive form. A 20-month-old boy was admitted to our hospital for close examination and treatment of his brain tumor. He had short stature, microcephaly, auricular deformity, and right renal hypoplasia seen on abdominal CT. Chemotherapy was started after partial resection. A cancer genome profile test detected a nonsense variant of the single-allelic BRCA2 gene in the tumor cells. He was highly suggestive of FA in combination with multiple dysmorphic features. Whole exome analysis using the peripheral lymphocytes identified variants of the BRCA2 gene (c.A7969T, p.K2657Ter and c.C7847T, p.S2616F) in a compound heterozygous manner. The uniallelic variant of the BRCA2 gene was found in each of the parents. The pathological variants obtained from tumor cells provided evidence for the diagnosis of an affected child, treatment decisions, and prognosis of life expectancy, as well as for preventive cancer surveillance of hereditary breast and ovarian cancer in the parents. In addition, it was useful for estimating recurrence rates with respect to FA-D1 in the next pregnancy. Genomic practice collaboration among multiple departments was useful, leading to genetic counseling across pediatric rare diseases, hereditary tumors, and prenatal diagnosis.