title: A case of progressing focal nodular hyperplasia and its molecular expression pattern.
abstract: We report the case of an adult male with progressing focal nodular hyperplasia (FNH). Although imaging studies suggested that the tumor was a classical FNH, the tumor biopsy showed glutamine synthetase expression and heat shock protein 70 in part of the tumor. As we could not definitely distinguish this case of FNH from early hepatocellular carcinoma (HCC), we performed laparoscopic partial hepatectomy. The surgical resected specimen showed that the tumor had a central scar with vascular and cholangiolar proliferation, which is compatible with FNH. Immunohistochemical analysis showed that the molecular expression pattern was compatible with FNH in the center of the tumor, whereas it partly resembled early HCC in the periphery of the tumor. FNH progression is occasionally found, and the molecular pattern of the progressing area in FNH might resemble that of early HCC due to morphologic and phenotypic changes induced by the regenerative mechanism and the alteration of blood flow. We should carefully observe progressing FNH.
authors.affiliation: Department of Gastroenterology, Toyama University Hospital, 2630 Sugitani, Toyama, 930-0194, Japan, tajikazu@med.u-toyama.ac.jp.
authors.forename: Kazuto
authors.initials: K
authors.lastname: Tajiri
authors.forename: Koichi
authors.initials: K
authors.lastname: Tsuneyama
authors.forename: Kengo
authors.initials: K
authors.lastname: Kawai
authors.forename: Yoshinari
authors.initials: Y
authors.lastname: Atarashi
authors.forename: Masami
authors.initials: M
authors.lastname: Minemura
authors.forename: Shigeaki
authors.initials: S
authors.lastname: Sawada
authors.forename: Kazuhiro
authors.initials: K
authors.lastname: Tsukada
authors.forename: Johji
authors.initials: J
authors.lastname: Imura
authors.forename: Toshiro
authors.initials: T
authors.lastname: Sugiyama
mesh_terms: D000328:Adult; D018450:Disease Progression; D020518:Focal Nodular Hyperplasia / Q000175:diagnosis* / Q000601:surgery; D006801:Humans; D008297:Male