title: Non-hypervascular hepatobiliary phase hypointense nodules on gadoxetic acid-enhanced MRI: risk of HCC recurrence after radiofrequency ablation.
abstract: OBJECTIVE
  Hepatobiliary phase images (HBPI) of gadoxetic acid-enhanced MRI can depict borderline hepatocellular nodules that have the potential to progress into hypervascular hepatocellular carcinomas (HCCs), as non-hypervascular hypointense nodules. We retrospectively evaluated the impact of the presence of non-hypervascular hypointense nodules at HBPI of gadoxetic acid-enhanced MRI on the patient's prognosis after radiofrequency ablation (RFA) for early stage HCCs.
  
  
  METHODS
  A total of 139 patients who underwent pre-procedural gadoxetic acid-enhanced MRI followed by RFA were included. After a mean follow-up of 44.6±13.2 months, we compared the results of tumor recurrence as well as overall and recurrence-free survival (RFS) with the presence of non-hypervascular hypointense nodules on HBPI.
  
  
  RESULTS
  The presence of non-hypervascular hypointense nodules on HBPI did not affect overall survival (p=0.136). However, the estimated 5-year RFS rate was 71.3% in 29 patients without non-hypervascular hypointense nodules on HBPI compared to 27.9% in 110 patients with non-hypervascular hypointense nodules on HBPI, indicating a significant difference (hazard ratio=2.84 [1.39-5.98], p=0.006). When we classified recurrence into local tumor progression [LTP], intrahepatic distant recurrence [IDR], and extra-hepatic metastasis [EM], five-year cumulative incidences (CI) of IDR in patients with non-hypervascular hypointense nodules on HBPI were significantly higher than those in patients without non-hypervascular hypointense nodules on HBPI (17.9% vs. 67.5%, p<0.001). Five-year CIs of LTP and EM showed no significant difference (p>0.05).
  
  
  CONCLUSIONS
  The presence of non-hypervascular hypointense hepatocellular nodules on HBPI of gadoxetic acid-enhanced MRI taken prior to RFA is a significant predictive factor of recurrence after RFA of early stage HCCs, particularly IDR.
authors.affiliation: Department of Radiology, Seoul National University Hospital, Republic of Korea.
authors.forename: Dong Ho
authors.initials: DH
authors.lastname: Lee
authors.affiliation: Department of Radiology, Seoul National University Hospital, Republic of Korea; Institute of Radiation Medicine, Seoul National University Hospital, Republic of Korea. Electronic address: jmsh@snu.ac.kr.
authors.forename: Jeong Min
authors.initials: JM
authors.lastname: Lee
authors.affiliation: Department of Radiology, Seoul National University Hospital, Republic of Korea; Institute of Radiation Medicine, Seoul National University Hospital, Republic of Korea.
authors.forename: Jae Young
authors.initials: JY
authors.lastname: Lee
authors.affiliation: Department of Radiology, Seoul National University Hospital, Republic of Korea; Institute of Radiation Medicine, Seoul National University Hospital, Republic of Korea.
authors.forename: Se Hyung
authors.initials: SH
authors.lastname: Kim
authors.affiliation: Department of Radiology, Seoul National University Hospital, Republic of Korea; Institute of Radiation Medicine, Seoul National University Hospital, Republic of Korea.
authors.forename: Jung Hoon
authors.initials: JH
authors.lastname: Kim
authors.affiliation: Department of Internal Medicine, Seoul National University Hospital, Republic of Korea.
authors.forename: Jung Hwan
authors.initials: JH
authors.lastname: Yoon
authors.affiliation: Department of Internal Medicine, Seoul National University Hospital, Republic of Korea.
authors.forename: Yoon Jun
authors.initials: YJ
authors.lastname: Kim
authors.affiliation: Department of Internal Medicine, Seoul National University Hospital, Republic of Korea.
authors.forename: Jeong-Hoon
authors.initials: JH
authors.lastname: Lee
authors.affiliation: Department of Internal Medicine, Seoul National University Hospital, Republic of Korea.
authors.forename: Su Jong
authors.initials: SJ
authors.lastname: Yu
authors.affiliation: Department of Radiology, Seoul National University Hospital, Republic of Korea; Institute of Radiation Medicine, Seoul National University Hospital, Republic of Korea.
authors.forename: Joon Koo
authors.initials: JK
authors.lastname: Han
authors.affiliation: Department of Radiology, Seoul National University Hospital, Republic of Korea; Institute of Radiation Medicine, Seoul National University Hospital, Republic of Korea.
authors.forename: Byung Ihn
authors.initials: BI
authors.lastname: Choi
mesh_terms: D006528:Carcinoma, Hepatocellular / Q000175:diagnosis / Q000473:pathology / Q000601:surgery; D017115:Catheter Ablation / Q000379:methods*; D003287:Contrast Media / Q000494:pharmacology; D005260:Female; D019786:Gadolinium DTPA / Q000494:pharmacology*; D006498:Hepatectomy / Q000379:methods*; D006801:Humans; D007089:Image Enhancement / Q000379:methods; D008113:Liver Neoplasms / Q000175:diagnosis / Q000473:pathology / Q000601:surgery; D008279:Magnetic Resonance Imaging / Q000379:methods; D008297:Male; D008875:Middle Aged; D009364:Neoplasm Recurrence, Local; D009367:Neoplasm Staging; D011237:Predictive Value of Tests; D011379:Prognosis
chemical_list: D003287:Contrast Media; C073590:gadolinium ethoxybenzyl DTPA; D019786:Gadolinium DTPA
keywords: Gadoxetic acid-enhanced MRI; Hepatocellular carcinoma; Non-hypervascular hypointense nodule; Radiofrequency ablation; Risk of recurrence