title: Intraosseous inflammatory myofibroblastic tumor of the mandible with a novel ATIC-ALK fusion mutation: a case report.
abstract: BACKGROUND
  Inflammatory myofibroblastic tumor (IMT) is a rare low-grade malignant neoplasm with a predilection for children and young adults, and typically arises in the lung, abdominopelvic region, and retroperitoneum. IMTs in the maxillofacial region are extreme rare. Approximately 50% of IMT harbor rearrangements of the anaplastic lymphoma kinase (ALK) gene at 2p23 with various fusion partners.
  
  
  METHODS
  We herein report a case of intraosseous IMT of the mandible with a novel ATIC-ALK fusion. Tooth 43 did not erupt after the loss of tooth 83 in an 11-year-old girl with no previous history of trauma. Panoramic tomography showed a unilocular radiolucent lesion in the right anterior mandible resorbing the root of tooth 42 and the medial side of the root of tooth 44. Computed tomography revealed a well- circumscribed 3-cm osteolytic lesion of the right anterior mandible eroding the buccal cortical plate. The entire lesion was curetted out. A histopathological examination revealed the proliferation of plump spindle cells with a storiform architecture and lymphocytes scattered around spindle cells. The spindle cells showed diffuse cytoplasmic staining for ALK by immunohistochemistry. A fluorescence in situ hybridization analysis revealed the translocation of a part of the ALK gene locus at chromosome 2p23. A rapid amplification of cDNA ends analysis confirmed the rearrangement of ALK and identified ATIC as a partner of this ALK fusion mutant.
  
  
  CONCLUSIONS
  To the best of our knowledge, this is the first case of intraosseous IMT of the mandible with a novel ATIC-ALK fusion. We also herein reviewed similar tumors reported in the literature.
authors.affiliation: Department of Pathology, Yokohama City University Graduate School of Medicine, Yokohama, Japan. ytateish@yokohama-cu.ac.jp.
authors.forename: Yoko
authors.initials: Y
authors.lastname: Tateishi
authors.affiliation: Department of Pathology, Yokohama City University Graduate School of Medicine, Yokohama, Japan.
authors.forename: Koji
authors.initials: K
authors.lastname: Okudela
authors.affiliation: Department of Pathology, Japanese Red-Cross Musashino Hospital, Tokyo, Japan.
authors.forename: Shigeo
authors.initials: S
authors.lastname: Kawai
authors.affiliation: Department of Pathology, Yokohama City University Graduate School of Medicine, Yokohama, Japan.
authors.forename: Takehisa
authors.initials: T
authors.lastname: Suzuki
authors.affiliation: Department of Pathology, Yokohama City University Graduate School of Medicine, Yokohama, Japan.
authors.forename: Shigeaki
authors.initials: S
authors.lastname: Umeda
authors.affiliation: Department of Pathology, Yokohama City University Graduate School of Medicine, Yokohama, Japan.
authors.forename: Mai
authors.initials: M
authors.lastname: Matsumura
authors.affiliation: Department of Oral and Maxillofacial Surgery, Yokohama City University Graduate School of Medicine, Yokohama, Japan.
authors.forename: Mitomu
authors.initials: M
authors.lastname: Kioi
authors.affiliation: Department of Pathology, Yokohama City University Graduate School of Medicine, Yokohama, Japan.
authors.forename: Kenichi
authors.initials: K
authors.lastname: Ohashi
mesh_terms: D014408:Biomarkers, Tumor / Q000032:analysis; D002648:Child; D005260:Female; D006104:Granuloma, Plasma Cell / Q000235:genetics* / Q000473:pathology; D006801:Humans; D007150:Immunohistochemistry; D017404:In Situ Hybridization, Fluorescence; D007249:Inflammation / Q000235:genetics / Q000473:pathology; D008336:Mandibular Diseases / Q000235:genetics* / Q000473:pathology; D015514:Oncogene Proteins, Fusion / Q000235:genetics*
chemical_list: C429803:ATIC-ALK fusion protein, human; D014408:Biomarkers, Tumor; D015514:Oncogene Proteins, Fusion
keywords: 5′ rapid amplification of cDNA ends; ATIC-ALK fusion; Anaplastic lymphoma kinase gene; Fluorescence in situ hybridization; Inflammatory myofibroblastic tumor; Mandible; RT-PCR