title: A hepatocellular neoplasm accompanied with massive histiocyte infiltration.
abstract: This report presents the case of a unique hepatocellular nodule occurring in a 73-year-old Japanese male with diabetes mellitus and mild obesity. The nodule consisted of hepatocyte-like tumor cells and abundant foam cell type histiocytes that filled up a sinusoid-like space and formed central loose fibrosis. The superficial area did not contain as many histiocytes and showed hepatocellular adenoma character, but there was a focal hepatocellular carcinoma-like lesion, thus suggesting hepatocellular adenoma with malignant transformation. The background liver showed an almost normal histology except for mild steatosis with no specific infiltration of macrophages. These macrophages contained abundant fat droplets, whereas the tumor cells had no fat droplets. The expressions of monocyte chemoattractant protein-1 and macrophage colony-stimulating factor were significantly higher in the tumor than in the background liver. These findings suggested such macrophage infiltration induced by the tumor cells and these macrophages probably phagocytosed surplus fat at the intercellular space of this unique tumor.
authors.affiliation: Department of Pathology and Biodefense, Saga University Faculty of Medicine, Nabesima 5-1-1, Saga, Saga, 849-8501, Japan. kaikeit@cc.saga-u.ac.jp.|Department of Surgery, Saga University Faculty of Medicine, Saga, Japan. kaikeit@cc.saga-u.ac.jp.
authors.forename: Keita
authors.initials: K
authors.lastname: Kai
authors.affiliation: Department of Surgery, Saga University Faculty of Medicine, Saga, Japan.
authors.forename: Atsushi
authors.initials: A
authors.lastname: Miyoshi
authors.affiliation: Department of Pathology and Biodefense, Saga University Faculty of Medicine, Nabesima 5-1-1, Saga, Saga, 849-8501, Japan.
authors.forename: Osamu
authors.initials: O
authors.lastname: Tokunaga
authors.affiliation: Department of Surgery, Saga University Faculty of Medicine, Saga, Japan.
authors.forename: Kenji
authors.initials: K
authors.lastname: Kitahara
authors.affiliation: Department of Surgery, Saga University Faculty of Medicine, Saga, Japan.
authors.forename: Tomohide
authors.initials: T
authors.lastname: Takahashi
authors.affiliation: Department of Surgery, Saga University Faculty of Medicine, Saga, Japan.
authors.forename: Shuusuke
authors.initials: S
authors.lastname: Miyake
authors.affiliation: Department of Radiology, Saga University Faculty of Medicine, Saga, Japan.
authors.forename: Yoshiaki
authors.initials: Y
authors.lastname: Egashira
authors.affiliation: Department of Radiology, Saga University Faculty of Medicine, Saga, Japan.
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Irie
authors.affiliation: Department of Surgery, Saga University Faculty of Medicine, Saga, Japan.
authors.forename: Hirokazu
authors.initials: H
authors.lastname: Noshiro
authors.affiliation: Department of Surgery, Saga University Faculty of Medicine, Saga, Japan.
authors.forename: Kohji
authors.initials: K
authors.lastname: Miyazaki
keywords: Hepatocellular adenoma; Hepatocellular carcinoma; Histiocyte; Macrophage colony-stimulating factor; Monocyte chemoattractant protein-1