title: Cystic changes in hepatic and peritoneal metastases from gastrointestinal stromal tumors treated with Gleevec.
abstract: BACKGROUND
  Tyrosine kinase inhibitor (Gleevec or STI-571) must be considered the treatment of choice for metastatic gastrointestinal stromal tumors (GISTs). The purpose of this article is to address and illustrate a long-term follow-up of computed tomographic (CT) radiologic findings in patients with metastases from GIST after Gleevec treatment.
  
  
  METHODS
  We performed a retrospective review of seven patients (four male, three female) with unresectable metastases from GIST who were treated with STI-571 in a 1-year period. Patients were followed every 2-4 months by contrast-enhanced CT for up to 12 months. The size and attenuation of hepatic and peritoneal metastases on CT were measured and correlated.
  
  
  RESULTS
  Hepatic metastases from GISTs showed significant decreased attenuation from a mean of 60 HU to a mean of 32 HU (p < 0.01) in the first 2 months and continued decreasing attenuation to 23 HU at the 12-month follow-up. These metastases superficially resembled simple cysts. Most metastases became smaller, with more defined borders, after treatment. Histologic examination in a resected specimen revealed hepatic cyst with no residual tumor cells, regression of omental lesions, and extensive necrosis.
  
  
  CONCLUSIONS
  CT findings of unresectable hepatic and peritoneal metastases from GIST displayed decreasing, near cystic attenuation and size as an effective regression in response to STI-571 treatment.
authors.affiliation: Department of Radiology, Wake Forest University School of Medicine, Medical Center Boulevard, Winston-Salem, NC 27157-1088, USA.
authors.forename: R E
authors.initials: RE
authors.lastname: Bechtold
authors.forename: M Y M
authors.initials: MY
authors.lastname: Chen
authors.forename: C A
authors.initials: CA
authors.lastname: Stanton
authors.forename: P D
authors.initials: PD
authors.lastname: Savage
authors.forename: E A
authors.initials: EA
authors.lastname: Levine
mesh_terms: D000328:Adult; D000368:Aged; D000970:Antineoplastic Agents / Q000627:therapeutic use*; D001549:Benzamides; D005260:Female; D005500:Follow-Up Studies; D005770:Gastrointestinal Neoplasms / Q000473:pathology*; D006801:Humans; D000068877:Imatinib Mesylate; D008113:Liver Neoplasms / Q000188:drug therapy* / Q000556:secondary*; D008297:Male; D008875:Middle Aged; D010534:Peritoneal Neoplasms / Q000188:drug therapy* / Q000556:secondary*; D010879:Piperazines / Q000627:therapeutic use*; D011505:Protein-Tyrosine Kinases / Q000037:antagonists & inhibitors*; D011743:Pyrimidines / Q000627:therapeutic use*; D012189:Retrospective Studies; D017154:Stromal Cells; D013997:Time Factors
chemical_list: D000970:Antineoplastic Agents; D001549:Benzamides; D010879:Piperazines; D011743:Pyrimidines; D000068877:Imatinib Mesylate; D011505:Protein-Tyrosine Kinases