title: Pseudolesion of the liver on gadoxetate disodium-enhanced MR images obtained after transarterial chemoembolization for hepatocellular carcinoma: clinicoradiologic correlation.
abstract: OBJECTIVE
  The purpose of this study was to elucidate the clinicoradiologic characteristics of pseudolesions of the liver in patients with hepatocellular carcinoma (HCC) treated with transarterial chemoembolization (TACE) as observed on gadoxetate disodium-enhanced MR images. A particular interest was correlation between the pseudolesion characteristics and TACE-MRI interval, during which sequential changes in pseudolesions may be revealed after TACE.
  
  
  METHODS
  Forty-eight patients with HCC who underwent gadoxetate disodium-enhanced MRI after TACE were retrospectively recruited. Pseudolesions were defined as areas of decreased signal intensity in treated areas on hepatocellular phase images that were confirmed to be nontumorous areas at follow-up. The prevalence and MRI features of pseudolesions were correlated with various clinical parameters, including TACE-MRI interval.
  
  
  RESULTS
  Pseudolesions were found in 14 patients (29%). Within 1 month of TACE, the prevalence of pseudolesions was 83%. All of the pseudolesions had arterial enhancement, mimicking residual HCC. After 1 month, the prevalence of pseudolesions decreased, and these pseudolesions tended to exhibit no abnormality in any sequence other than the hepatocellular phase. Results of multivariate analysis suggested that size of HCC (p < 0.0001), duration of postembolization syndrome (p = 0.012), and TACE-MRI interval (p = 0.038) are independent indicators of the presence of pseudolesions.
  
  
  CONCLUSIONS
  The prevalence and appearance of pseudolesions differ at different intervals from TACE. Radiologists need to recognize the clinicoradiologic characteristics to differentiate pseudolesions from true residual or recurrent HCC.
authors.affiliation: Department of Radiology, Faculty of Medicine, Fukuoka University, 7-45-1, Nanakuma, Johnan-ku, Fukuoka, 814-0180, Japan.
authors.forename: Yoshinobu
authors.initials: Y
authors.lastname: Shinagawa
authors.forename: Keiko
authors.initials: K
authors.lastname: Sakamoto
authors.forename: Ritsuko
authors.initials: R
authors.lastname: Fujimitsu
authors.forename: Mikiko
authors.initials: M
authors.lastname: Shimakura
authors.forename: Shin-ichi
authors.initials: S
authors.lastname: Kora
authors.forename: Koichi
authors.initials: K
authors.lastname: Takano
authors.forename: Kengo
authors.initials: K
authors.lastname: Yoshimitsu
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D000970:Antineoplastic Agents / Q000008:administration & dosage; D006528:Carcinoma, Hepatocellular / Q000473:pathology* / Q000628:therapy*; D016461:Chemoembolization, Therapeutic / Q000379:methods*; D003287:Contrast Media; D005260:Female; D019786:Gadolinium DTPA; D006801:Humans; D008113:Liver Neoplasms / Q000473:pathology* / Q000628:therapy*; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D008875:Middle Aged; D012189:Retrospective Studies; D018709:Statistics, Nonparametric; D016896:Treatment Outcome
chemical_list: D000970:Antineoplastic Agents; D003287:Contrast Media; C073590:gadolinium ethoxybenzyl DTPA; D019786:Gadolinium DTPA