title: Computed tomography and magnetic resonance imaging of a plexiform angiomyxoid myofibroblastic tumor: a case report.
abstract: Plexiform angiomyxoid myofibroblastic tumor (PAMT) is a very rare mesenchymal tumor of the stomach. Here we report a case of pathologically confirmed PAMT with an unique cyst formation.
  
  
  
  A 55-year-old male with a 10-year history of a gastric subepithelial tumor underwent computed tomography (CT) and magnetic resonance imaging (MRI). Two cysts were observed in the tumor, and the cyst wall showed moderately high intensity on T2-weighted images compared with the gastric wall. On dynamic study, the cyst wall showed a gradual enhancement pattern, and prominent enhancement was observed in the delayed phase. Laparoscopic partial gastric resection was performed, and a pathological diagnosis of PAMT was rendered.
  
  
  
  We present a rare case of gastric PAMT, which was uniquely presented as cysts. One of the cysts in the tumor had an epithelial wall lining, which had never been reported before in gastric mesenchymal tumor, in addition to partial glandular structure. We reviewed our case, focusing on radiologic-pathologic correlation, and suggested hypothesis of cyst formation. According to our findings, PAMT with cyst formation would be included of differential diagnosis of gastric subepithelial tumors.
authors.affiliation: Department of Radiology, Institute of Medical Science, University of Tokyo, 4-6-1 Shirokanedai, Minato-ku, Tokyo, 108-8639, Japan. hakai-tky@umin.ac.jp.
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Akai
authors.affiliation: Department of Radiology, Institute of Medical Science, University of Tokyo, 4-6-1 Shirokanedai, Minato-ku, Tokyo, 108-8639, Japan.
authors.forename: Shigeru
authors.initials: S
authors.lastname: Kiryu
authors.affiliation: Department of Surgery, Institute of Medical Science, University of Tokyo, 4-6-1 Shirokanedai, Minato-ku, Tokyo, 108-8639, Japan.
authors.forename: Masaru
authors.initials: M
authors.lastname: Shinozaki
authors.affiliation: Department of Pathology, Institute of Medical Science, University of Tokyo, 4-6-1 Shirokanedai, Minato-ku, Tokyo, 108-8639, Japan.
authors.forename: Yasunori
authors.initials: Y
authors.lastname: Ohta
authors.affiliation: Department of Radiology, Institute of Medical Science, University of Tokyo, 4-6-1 Shirokanedai, Minato-ku, Tokyo, 108-8639, Japan.
authors.forename: Yoshiyasu
authors.initials: Y
authors.lastname: Nakano
authors.affiliation: Department of Radiology, Institute of Medical Science, University of Tokyo, 4-6-1 Shirokanedai, Minato-ku, Tokyo, 108-8639, Japan.
authors.forename: Koichiro
authors.initials: K
authors.lastname: Yasaka
authors.affiliation: Department of Radiology, Graduate School of Medicine, University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo, 113-8655, Japan.
authors.forename: Kuni
authors.initials: K
authors.lastname: Ohtomo
mesh_terms: D003937:Diagnosis, Differential; D046152:Gastrointestinal Stromal Tumors / Q000000981:diagnostic imaging*; D006801:Humans; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D008875:Middle Aged; D064847:Multimodal Imaging; D058628:Myofibroblasts / Q000473:pathology*; D009232:Myxoma / Q000000981:diagnostic imaging*; D013274:Stomach Neoplasms / Q000000981:diagnostic imaging*; D014057:Tomography, X-Ray Computed / Q000379:methods*; D047368:Tumor Burden
keywords: Computed tomography; Magnetic resonance imaging; Mesenchymal tumor; Stomach