title: Synchronous multicentric small hepatocellular carcinomas: defining the capsule on high-frequency intraoperative ultrasonography with pathologic correlation.
abstract: OBJECTIVE
  The aim of this study was to define the capsules of synchronous multicentric small hepatocellular carcinomas (HCCs) with use of high-frequency intraoperative ultrasonography (IOUS).
  
  
  METHODS
  Among the 131 consecutive patients undergoing hepatic resection and high-frequency IOUS for HCC, 16 synchronous multicentric small HCCs in 13 patients were histologically diagnosed in the resected specimens. High-frequency IOUS and pathologic findings of these lesions were compared, with particular focus on the presence and appearance of the capsule in or around each lesion.
  
  
  RESULTS
  Synchronous multicentric small HCCs were pathologically classified into distinctly nodular (n=12) or vaguely nodular (n=4) types. All 12 distinctly nodular HCCs including six subcentimeter lesions showed detectable capsules on high-frequency IOUS and pathology. The capsules appeared as a hypoechoic rim containing hyperechoic foci (n=6), hypoechoic rim (n=5), or hyperechoic rim (n=1) with varying degrees of coverage around each lesion. Histologically, the capsules were composed of a combination of one to four layers consisting of a fibrous capsule, peritumoral fibrosis, prominent small vessels, and entrapped hepatic parenchyma.
  
  
  CONCLUSIONS
  Synchronous multicentric small HCCs with distinctly nodular type, even at subcentimeter size, can show capsules with varying coverage and diverse echogenicity on high-frequency IOUS.
authors.affiliation: Department of Radiology, Gangneung Asan Hospital, University of Ulsan College of Medicine, Gangneung, Korea.
authors.forename: Jae Hong
authors.identifier: 0000-0003-4164-1974
authors.initials: JH
authors.lastname: Ahn
authors.affiliation: Department of Pathology, Gangneung Asan Hospital, University of Ulsan College of Medicine, Gangneung, Korea.
authors.forename: Dae-Woon
authors.identifier: 0000-0001-9718-996X
authors.initials: DW
authors.lastname: Eom
authors.affiliation: Department of Radiology, Gangneung Asan Hospital, University of Ulsan College of Medicine, Gangneung, Korea.
authors.forename: Dae Shick
authors.identifier: 0000-0001-6590-720X
authors.initials: DS
authors.lastname: Ryu
authors.affiliation: Department of Radiology, Gangneung Asan Hospital, University of Ulsan College of Medicine, Gangneung, Korea.
authors.forename: Man Soo
authors.identifier: 0000-0002-9511-8129
authors.initials: MS
authors.lastname: Park
authors.affiliation: Department of Radiology, Gangneung Asan Hospital, University of Ulsan College of Medicine, Gangneung, Korea.
authors.forename: Seung Mun
authors.identifier: 0000-0001-6389-2315
authors.initials: SM
authors.lastname: Jung
authors.affiliation: Department of Surgery, Gangneung Asan Hospital, University of Ulsan College of Medicine, Gangneung, Korea.
authors.forename: Kun Moo
authors.identifier: 0000-0003-3889-3484
authors.initials: KM
authors.lastname: Choi
authors.affiliation: Department of Hepatology, Gangneung Asan Hospital, University of Ulsan College of Medicine, Gangneung, Korea.
authors.forename: Gab Jin
authors.identifier: 0000-0001-5937-5999
authors.initials: GJ
authors.lastname: Cheon
authors.affiliation: Department of Radiology, Gangneung Asan Hospital, University of Ulsan College of Medicine, Gangneung, Korea.
authors.forename: Soo-Jung
authors.identifier: 0000-0003-0437-6657
authors.initials: SJ
authors.lastname: Choi
authors.affiliation: Department of Surgery, Gangneung Asan Hospital, University of Ulsan College of Medicine, Gangneung, Korea.
authors.forename: Hyuk Jai
authors.identifier: 0000-0002-7777-275X
authors.initials: HJ
authors.lastname: Jang
keywords: Carcinoma, hepatocellular; Liver neoplasms; Ultrasonography