title: Optimization of imaging diagnosis of 1-2 cm hepatocellular carcinoma: an analysis of diagnostic performance and resource utilization.
abstract: OBJECTIVE
  To determine the optimal imaging scan or combinations in terms of diagnostic performance and resource utilization for 1-2 cm nodules found on surveillance for hepatocellular carcinoma.
  
  
  METHODS
  Eighty-four cirrhotic patients with 101, 1-2 cm nodules (34 malignant, 67 non-malignant) prospectively underwent standardized contrast-enhanced ultrasound, CT, and MRI scans. Sensitivity/specificity and potential imaging/biopsy utilization of individual imaging modalities and two-modality combinations performed at the same time (coincidental) or in sequence were measured. Final diagnosis was determined by biopsy (23), growth (10), recurrence (1), or stability in size for ≥ 18 months (67).
  
  
  RESULTS
  For single imaging scans, sensitivities/specificities ranged between 53-62% and 91-100%. When two scans were combined requiring both to be positive, sensitivities/specificities ranged between 29-41% and 99-100%. When two scans were combined sequentially, requiring only one to be positive, sensitivities/specificities ranged between 74-89% and 91-99%. When comparing combination of two positive tests (MRI and CT) to MRI alone, there was a significant drop in sensitivity (41% vs. 62%, p=0.02), no change in specificity (both 100%), with twice as many scans performed, and 9% rise in potential biopsies or 7% rise in follow-up scans. When comparing the combination of MRI then CT (if MRI negative) to MRI alone, there was an insignificant rise in sensitivity (74% vs. 62%, p=0.13), drop in specificity (97% vs. 100%), with 77% more scans performed, and 6% drop in potential biopsies or 7% drop in potential follow-up scans.
  
  
  CONCLUSIONS
  Single imaging scans have similar specificity to two coincidental positive scans with much less resource utilization. Sequential imaging provides the best sensitivity but with diminished specificity.
authors.affiliation: Department of Medical Imaging, University of Toronto, Canada. korosh.khalili@uhn.on.ca
authors.forename: Korosh
authors.initials: K
authors.lastname: Khalili
authors.forename: Tae Kyoung
authors.initials: TK
authors.lastname: Kim
authors.forename: Hyun-Jung
authors.initials: HJ
authors.lastname: Jang
authors.forename: Masoom A
authors.initials: MA
authors.lastname: Haider
authors.forename: Luluel
authors.initials: L
authors.lastname: Khan
authors.forename: Maha
authors.initials: M
authors.lastname: Guindi
authors.forename: Morris
authors.initials: M
authors.lastname: Sherman
mesh_terms: D000328:Adult; D000368:Aged; D006528:Carcinoma, Hepatocellular / Q000175:diagnosis* / Q000000981:diagnostic imaging / Q000473:pathology*; D003287:Contrast Media; D005260:Female; D006801:Humans; D008103:Liver Cirrhosis / Q000000981:diagnostic imaging / Q000473:pathology; D008113:Liver Neoplasms / Q000175:diagnosis* / Q000000981:diagnostic imaging / Q000473:pathology*; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D017410:Practice Guidelines as Topic; D011446:Prospective Studies; D014057:Tomography, X-Ray Computed; D014463:Ultrasonography; D055815:Young Adult
chemical_list: D003287:Contrast Media