title: Does Establishing a Safety Margin Reduce Local Recurrence in Subsegmental Transarterial Chemoembolization for Small Nodular Hepatocellular Carcinomas?
abstract: OBJECTIVE
  To test the hypothesis that a safety margin may affect local tumor recurrence (LTR) in subsegmental chemoembolization.
  
  
  METHODS
  In 101 patients with 128 hepatocellular carcinoma (HCC) nodules (1-3 cm in size and ≤ 3 in number), cone-beam CT-assisted subsegmental lipiodol chemoembolization was performed. Immediately thereafter, a non-contrast thin-section CT image was obtained to evaluate the presence or absence of intra-tumoral lipiodol uptake defect and safety margin. The effect of lipiodol uptake defect and safety margin on LTR was evaluated. Univariate and multivariate analyses were performed to indentify determinant factors of LTR.
  
  
  RESULTS
  Of the 128 HCC nodules in 101 patients, 49 (38.3%) nodules in 40 patients showed LTR during follow-up period (median, 34.1 months). Cumulative 1- and 2-year LTR rates of nodules with lipiodol uptake defect (n = 27) and those without defect (n = 101) were 58.1% vs. 10.1% and 72.1% vs. 19.5%, respectively (p < 0.001). Among the 101 nodules without a defect, the 1- and 2-year cumulative LTR rates for nodules with complete safety margin (n = 52) and those with incomplete safety margin (n = 49) were 9.8% vs. 12.8% and 18.9% vs. 19.0% (p = 0.912). In multivariate analyses, ascites (p = 0.035), indistinct tumor margin on cone-beam CT (p = 0.039), heterogeneous lipiodol uptake (p = 0.023), and intra-tumoral lipiodol uptake defect (p < 0.001) were determinant factors of higher LTR.
  
  
  CONCLUSIONS
  In lipiodol chemoembolization, the safety margin in completely lipiodolized nodule without defect will not affect LTR in small nodular HCCs.
authors.affiliation: Department of Radiology, Seoul National University Hospital, Seoul 03080, Korea. ; Department of Radiology, Seoul National University College of Medicine, Seoul 03080, Korea.
authors.forename: Hyo-Jin
authors.initials: HJ
authors.lastname: Kang
authors.affiliation: Department of Radiology, Seoul National University Hospital, Seoul 03080, Korea. ; Institute of Radiation Medicine, Seoul National University Medical Research Center, Seoul 03080, Korea. ; Biomedical Research Institute, Seoul National University Hospital, Seoul 03080, Korea. ; Department of Radiology, Sheikh Khalifa Specialty Hospital, Ras Al Khaimah, United Arab Emirates.
authors.forename: Young Il
authors.initials: YI
authors.lastname: Kim
authors.affiliation: Department of Radiology, Seoul National University Hospital, Seoul 03080, Korea. ; Department of Radiology, Seoul National University College of Medicine, Seoul 03080, Korea. ; Institute of Radiation Medicine, Seoul National University Medical Research Center, Seoul 03080, Korea.
authors.forename: Hyo-Cheol
authors.initials: HC
authors.lastname: Kim
authors.affiliation: Department of Radiology, Seoul National University Hospital, Seoul 03080, Korea. ; Department of Radiology, Seoul National University College of Medicine, Seoul 03080, Korea. ; Institute of Radiation Medicine, Seoul National University Medical Research Center, Seoul 03080, Korea.
authors.forename: Hwan Jun
authors.initials: HJ
authors.lastname: Jae
authors.affiliation: Department of Radiology, Seoul National University Hospital, Seoul 03080, Korea. ; Department of Radiology, Seoul National University College of Medicine, Seoul 03080, Korea.
authors.forename: Saebeom
authors.initials: S
authors.lastname: Hur
authors.affiliation: Department of Radiology, Seoul National University Hospital, Seoul 03080, Korea. ; Department of Radiology, Seoul National University College of Medicine, Seoul 03080, Korea. ; Institute of Radiation Medicine, Seoul National University Medical Research Center, Seoul 03080, Korea.
authors.forename: Jin Wook
authors.initials: JW
authors.lastname: Chung
mesh_terms: D000328:Adult; D000368:Aged; D006528:Carcinoma, Hepatocellular / Q000000981:diagnostic imaging / Q000628:therapy*; D016461:Chemoembolization, Therapeutic; D054893:Cone-Beam Computed Tomography; D004998:Ethiodized Oil / Q000008:administration & dosage*; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008113:Liver Neoplasms / Q000000981:diagnostic imaging / Q000628:therapy*; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D009364:Neoplasm Recurrence, Local / Q000000981:diagnostic imaging
chemical_list: D004998:Ethiodized Oil
keywords: Cone-beam CT; Hepatocellular carcinoma; Local tumor recurrence; Safety margin; Subsegmental transarterial chemoembolization