title: The effect of catheter-directed CT angiography on yttrium-90 radioembolization treatment of hepatocellular carcinoma.
abstract: OBJECTIVE
  Yttrium 90 radioembolization is a transcatheter therapy for unresectable hepatocellular carcinoma (HCC) that delivers internal radiation to tumors. In contrast to the usual method of lobar regional delivery, catheter-directed computed tomographic (CT) angiography was investigated as a potentially useful technique to evaluate the administration of segmental 90Y tumor radiation doses superselectively without significantly altering liver function or Child-Pugh classification.
  
  
  METHODS
  Fourteen patients underwent 90Y therapy for unresectable HCC. After standard angiographic placement of a 3-F microcatheter in a segmental hepatic artery supplying the tumor, each patient underwent CT angiography with use of segmental hepatic artery injection of iodinated contrast agent to confirm segmental perfusion and delineate segmental liver volume. 90Y was later injected into the same segmental artery. Target dose was calculated according to infused 90Y activity and targeted hepatic volume with standard lobar volume (before CT angiography) versus segmental liver volume (after CT angiography). The Wilcoxon signed-rank test (alpha = 0.05) was used to compare the estimated 90Y dose before CT angiography with the actual 90Y dose after CT angiography, as well as changes in serum bilirubin level and Child-Pugh classification as a result of treatment.
  
  
  RESULTS
  The mean estimated tumor dose before CT angiography (SD) was 100 Gy +/- 43 (range, 35-169 Gy). The mean actual tumor dose after CT angiography was 348 Gy +/- 204 (range, 105-857 Gy), which was significantly greater (P < .001). The mean bilirubin level before treatment was 1.0 mg/dL +/- 0.97 (range, 0.2-4.0 mg/dL), whereas the mean bilirubin level after treatment was 1.3 mg/dL +/- 0.85 (range, 0.5-3.8 mg/dL). This difference, although statistically significant (P = .03), was not clinically important. Thirteen of 14 patients had no change in Child-Pugh class.
  
  
  CONCLUSIONS
  CT angiography can be used to delineate the blood supply and volume to a targeted hepatic segment, allowing superselective 90Y radioembolization. This approach significantly increases effective 90Y tumor radiation dose without clinically altering liver function or Child-Pugh class.
authors.affiliation: Section of Interventional Radiology, Department of Radiology, Henry Ford Hospital, Detroit, MI, USA.
authors.forename: Thomas K
authors.initials: TK
authors.lastname: Rhee
authors.forename: Reed A
authors.initials: RA
authors.lastname: Omary
authors.forename: Vanessa
authors.initials: V
authors.lastname: Gates
authors.forename: Taofic
authors.initials: T
authors.lastname: Mounajjed
authors.forename: Andrew C
authors.initials: AC
authors.lastname: Larson
authors.forename: Omar
authors.initials: O
authors.lastname: Barakat
authors.forename: Kent T
authors.initials: KT
authors.lastname: Sato
authors.forename: Mary
authors.initials: M
authors.lastname: Mulcahy
authors.forename: Stuart
authors.initials: S
authors.lastname: Gordon
authors.forename: Robert J
authors.initials: RJ
authors.lastname: Lewandowski
authors.forename: Riad
authors.initials: R
authors.lastname: Salem
mesh_terms: D000328:Adult; D000368:Aged; D000792:Angiography; D006528:Carcinoma, Hepatocellular / Q000098:blood supply / Q000532:radiotherapy*; D004621:Embolization, Therapeutic / Q000379:methods; D005260:Female; D006499:Hepatic Artery; D006801:Humans; D007269:Injections, Intra-Arterial; D008113:Liver Neoplasms / Q000098:blood supply / Q000532:radiotherapy*; D008297:Male; D008875:Middle Aged; D015641:Radiography, Interventional; D019275:Radiopharmaceuticals / Q000008:administration & dosage* / Q000627:therapeutic use; D011879:Radiotherapy Dosage; D014057:Tomography, X-Ray Computed; D015021:Yttrium Radioisotopes / Q000008:administration & dosage* / Q000627:therapeutic use
chemical_list: D019275:Radiopharmaceuticals; D015021:Yttrium Radioisotopes