title: Delayed enhancement of hepatocellular carcinoma on dynamic CT: sign of extrahepatic collaterals after transcatheter arterial chemoembolization or transcatheter arterial chemoinfusion.
abstract: BACKGROUND
  We examined the factors of delayed enhancement of hepatocellular carcinoma (HCC) on dynamic computed tomography (CT).
  
  
  METHODS
  Dynamic CT and angiography were compared in 113 patients who had undergone transcatheter arterial chemoembolization or transcatheter arterial chemoinfusion and were suspected of developing new HCCs.
  
  
  RESULTS
  Eight of 113 patients had HCC nodules that enhanced gradually from the arterial phase to the portal venous phase on dynamic CT and were fed by extrahepatic arteries on angiography. The feeding artery was an omental branch of the splenic artery in one lesion, an omental branch of the gastroduodenal artery in five, and the intercostal artery in two.
  
  
  CONCLUSIONS
  We believe that the recurrence of HCCs delayed enhancement on dynamic CT because the hepatic artery was hidden and long narrow extrahepatic collaterals fed the tumor.
authors.affiliation: Department of Radiology, Sumitomo-Besshi Hospital, 3-1, Ohji, Niihama City, Ehime, 792-8543, Japan.
authors.forename: T
authors.initials: T
authors.lastname: Katoh
authors.forename: M
authors.initials: M
authors.lastname: Mitani
authors.forename: K
authors.initials: K
authors.lastname: Noma
authors.forename: T
authors.initials: T
authors.lastname: Sunayama
authors.forename: S
authors.initials: S
authors.lastname: Nakano
authors.forename: Y
authors.initials: Y
authors.lastname: Toyama
authors.forename: M
authors.initials: M
authors.lastname: Ohkawa
mesh_terms: D000368:Aged; D000792:Angiography; D006528:Carcinoma, Hepatocellular / Q000098:blood supply / Q000000981:diagnostic imaging*; D002404:Catheterization; D016461:Chemoembolization, Therapeutic; D005260:Female; D006801:Humans; D007089:Image Enhancement; D008113:Liver Neoplasms / Q000098:blood supply / Q000000981:diagnostic imaging*; D008297:Male; D014057:Tomography, X-Ray Computed / Q000379:methods*