title: Development of hepatocellular carcinomas in patients with absence of tumors on a prior ultrasound examination.
abstract: BACKGROUND
  To evaluate hepatocellular carcinoma (HCC) that developed in patients with no evidence of a tumor during a prior ultrasound (US) performed within 1 year of the diagnosis.
  
  
  METHODS
  We retrospectively analyzed data for 100 consecutive patients with liver cirrhosis who had undergone US within 1 year prior to HCC diagnosis and who showed no liver lesions on the previous US. Size and T stage of HCC were assessed as well as whether patients met surgical criteria for liver transplantation as HCC treatment [Milan or University of California at San Francisco (UCSF) criteria].
  
  
  RESULTS
  The mean interval between the negative and diagnostic scans was 5 months, 13 days. HCC presented as a single nodule in 69 patients (size, 0.8-8.0 cm), as two or more nodules in 18 patients, and as the diffuse form of HCC in 13 patients. HCC presented as a small tumor (<3 cm) in 48 patients. T stages were: T1 in 26 patients, T2 in 45, T3 in 18, and T4 in 11. The Milan criteria were met in 79 patients. Eighty-five patients fulfilled the UCSF.
  
  
  CONCLUSIONS
  Patients may present with advanced HCC, even if sonographic findings were negative within 1 year prior to diagnosis.
authors.affiliation: Department of Radiology, Yonsei University College of Medicine, Seodaemun-ku, Shinchon-dong 134, Seoul 120-752, Republic of Korea.
authors.forename: Kyung Ah
authors.initials: KA
authors.lastname: Kim
authors.forename: Myeong-Jin
authors.initials: MJ
authors.lastname: Kim
authors.forename: Jin-Young
authors.initials: JY
authors.lastname: Choi
authors.forename: Yong Eun
authors.initials: YE
authors.lastname: Chung
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D006528:Carcinoma, Hepatocellular / Q000000981:diagnostic imaging* / Q000473:pathology; D005260:Female; D006801:Humans; D008103:Liver Cirrhosis / Q000000981:diagnostic imaging*; D008113:Liver Neoplasms / Q000000981:diagnostic imaging* / Q000473:pathology; D016031:Liver Transplantation; D008297:Male; D008875:Middle Aged; D009367:Neoplasm Staging; D012189:Retrospective Studies; D012307:Risk Factors; D014057:Tomography, X-Ray Computed; D014463:Ultrasonography