title: Esophageal gastrointestinal stromal tumor: report of 7 patients.
abstract: OBJECTIVE
  To evaluate imaging features of esophageal gastrointestinal stromal tumors (GIST) with clinical and histopathologic correlation and imaging follow-up.
  
  
  METHODS
  In this institutional review board-approved, Health Insurance Portability and Accountability Act-compliant retrospective study, 14 patients with pathologically proven esophageal GIST seen from January 2001 to October 2011, 7 patients (4 women; mean age 70 years, range 56-87 years) who had imaging of primary tumor and follow-up imaging at our institution were included. Imaging studies were evaluated by 3 radiologists in consensus. Location, size and imaging features of primary tumor and metastases, if any, were recorded, and correlated with pathologic (histopathologic subtype, presence of necrosis, mitotic rate, immunohistochemical profile) and clinical (treatment-related changes, distant spread and outcome) parameters.
  
  
  RESULTS
  Of 7 tumors, 5 were located in the lower esophagus and 2 in mid-esophagus. Four were intraluminal, 2 were exophytic, and 1 was intramural. All 7 patients underwent computed tomography (CT); tumors appeared as well-circumscribed, hypoattenuating masses showing mild enhancement, with mean size of 5.7 × 4.2 cm. Necrosis and calcification were seen in 1 tumor each. Five patients underwent fluorodeoxyglucose (FDG)-positron emission tomography (PET)/CT. GISTs were FDG avid with mean standardized uptake value (SUV)[max] of 9.5 (4.5-12.3). All tumors were positive for KIT (7/7) and CD34 (6/6). Distant metastases to liver and pleura were seen in 1 patient. On imatinib treatment, the tumors responded with decreased attenuation values and unchanged size on CT, and decreased SUV[max] of primary tumor and metastases on FDG-PET/CT.
  
  
  CONCLUSIONS
  Esophageal GISTs are well-circumscribed, FDG-avid, hypoattenuating masses that can metastasize to liver and pleura, and respond to imatinib treatment with decreased attenuation value on CT and decreased SUV[max] on FDG-PET/CT.
authors.affiliation: Department of Imaging, Dana-Farber Cancer Institute, 450 Brookline Ave, Boston, MA 02115, USA. ashinagare@partners.org
authors.forename: A B
authors.initials: AB
authors.lastname: Shinagare
authors.forename: K A
authors.initials: KA
authors.lastname: Zukotynski
authors.forename: K M
authors.initials: KM
authors.lastname: Krajewski
authors.forename: J P
authors.initials: JP
authors.lastname: Jagannathan
authors.forename: J
authors.initials: J
authors.lastname: Butrynski
authors.forename: J L
authors.initials: JL
authors.lastname: Hornick
authors.forename: N H
authors.initials: NH
authors.lastname: Ramaiya
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D000970:Antineoplastic Agents / Q000627:therapeutic use; D001549:Benzamides; D017024:Chemotherapy, Adjuvant; D003131:Combined Modality Therapy; D057286:Electronic Health Records; D004938:Esophageal Neoplasms / Q000000981:diagnostic imaging* / Q000188:drug therapy / Q000473:pathology / Q000601:surgery; D016629:Esophagectomy; D005260:Female; D005462:Fluorine Radioisotopes; D019788:Fluorodeoxyglucose F18; D005500:Follow-Up Studies; D046152:Gastrointestinal Stromal Tumors / Q000000981:diagnostic imaging* / Q000188:drug therapy / Q000473:pathology / Q000601:surgery; D006801:Humans; D000068877:Imatinib Mesylate; D033162:Incidental Findings; D008297:Male; D008875:Middle Aged; D064847:Multimodal Imaging; D020360:Neoadjuvant Therapy; D016609:Neoplasms, Second Primary / Q000175:diagnosis; D010879:Piperazines / Q000627:therapeutic use; D049268:Positron-Emission Tomography; D011743:Pyrimidines / Q000627:therapeutic use; D019275:Radiopharmaceuticals; D012189:Retrospective Studies; D014057:Tomography, X-Ray Computed; D016896:Treatment Outcome
chemical_list: D000970:Antineoplastic Agents; D001549:Benzamides; D005462:Fluorine Radioisotopes; D010879:Piperazines; D011743:Pyrimidines; D019275:Radiopharmaceuticals; D019788:Fluorodeoxyglucose F18; D000068877:Imatinib Mesylate