title: Medulloblastoma with adverse reaction to radiation therapy in nijmegen breakage syndrome.
abstract: A 3-year-old child with microcephaly, facial dysmorphism, growth retardation, and developmental delay was diagnosed with medulloblastoma. Craniospinal irradiation resulted in severe radiation-induced dermatitis and gastroesophagitis, unresponsive to further medical therapy. Colony survival assay on the patient's transformed lymphocytes revealed a high degree of radiosensitivity ex vivo. The presence of radiation sensitivity, both clinically and ex vivo, in association with microcephaly and growth retardation, prompted a diagnostic workup for Nijmegen breakage syndrome. The patient was confirmed to have a compound heterozygote genotype for the common founder mutation of NBS1 675del5 in exon 6, and 1142delC in exon 10. Because irradiation is an important component of therapy for brain tumors, caution should be exercised in cancer patients with associated microcephaly and growth retardation, as they may turn out to have the rare diagnosis of Nijmegen breakage syndrome.
authors.affiliation: Division of Pediatric Hematology-Oncology, Children's Hospital of Michigan, Detroit, Michigan 48201, USA.
authors.forename: Sameer
authors.initials: S
authors.lastname: Bakhshi
authors.forename: Karen M
authors.initials: KM
authors.lastname: Cerosaletti
authors.forename: Patrick
authors.initials: P
authors.lastname: Concannon
authors.forename: Erawati V
authors.initials: EV
authors.lastname: Bawle
authors.forename: James
authors.initials: J
authors.lastname: Fontanesi
authors.forename: Richard A
authors.initials: RA
authors.lastname: Gatti
authors.forename: Kanta
authors.initials: K
authors.lastname: Bhambhani
mesh_terms: D002528:Cerebellar Neoplasms / Q000532:radiotherapy*; D002675:Child, Preschool; D019457:Chromosome Breakage; D025063:Chromosome Disorders / Q000150:complications*; D005145:Face / Q000002:abnormalities; D006130:Growth Disorders / Q000235:genetics; D006801:Humans; D008607:Intellectual Disability / Q000235:genetics; D008297:Male; D008527:Medulloblastoma / Q000532:radiotherapy*; D011878:Radiotherapy / Q000009:adverse effects*