title: Hepatoid carcinoma of the skin: spontaneous rat skin hepatoid carcinoma with eosinophilic globules and crystals immunoreactive to alpha-1-antitrypsin.
abstract: We present a case of hepatoid carcinoma of the abdominal skin in a male Wistar rat. Histopathologically, this carcinoma resembled human hepatocellular carcinoma with respect to trabecular-sinusoidal structures. Carcinoma tissues contain numerous eosinophilic globules and crystals, and in this case, we found the characteristic eosinophilic globules in the hepatoid carcinoma cells and the crystals in the extracellular portions. Vivid carcinoma cells full of eosinophilic globules were present near the necrotic areas in tumor tissue, wherein quadrate crystals unstained with eosin were observed. PAS staining after diastase digestion revealed that the globules were PAS positive and diastase resistant. In addition, we found that the hepatoid carcinoma cells were immunoreactive for alpha-1-antitrypsin (anti-A1AT) antibody with the globules and crystals staining peripherally, and a central unstained region. Ultrastructural study of intracytoplasmic globules and extracellular crystals revealed that the fringe of each globule and crystal had no limiting membrane and showed the same level of electron density. These findings suggest that the characteristic crystals in this tumor may have originated from the globules that were emitted from the carcinoma cells after their death as a result of saturation with intracytoplasmic globules.
authors.affiliation: Oyokyo Kidney Research Institute, 90 Yamazaki Kozawa, Hirosaki, 036-8243, Japan. sutoh@oyokyo.jp
authors.forename: Mihoko
authors.initials: M
authors.lastname: Sutoh
authors.forename: Mitsuru
authors.initials: M
authors.lastname: Chiba
authors.forename: Kosuke
authors.initials: K
authors.lastname: Kasai
authors.forename: Tomisato
authors.initials: T
authors.lastname: Miura
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Nozaka
authors.forename: Kiyotada
authors.initials: K
authors.lastname: Washiya
authors.forename: Etsuko
authors.initials: E
authors.lastname: Okusawa
authors.forename: Naoto
authors.initials: N
authors.lastname: Oyama
authors.forename: Chikako
authors.initials: C
authors.lastname: Tsutaya
authors.forename: Megumi
authors.initials: M
authors.lastname: Tsushima
authors.forename: Yuriko
authors.initials: Y
authors.lastname: Terayama
authors.forename: Tomihisa
authors.initials: T
authors.lastname: Funyu
authors.forename: Tatsusuke
authors.initials: T
authors.lastname: Sato
mesh_terms: D000008:Abdominal Neoplasms / Q000276:immunology / Q000473:pathology* / Q000648:ultrastructure; D000818:Animals; D006528:Carcinoma, Hepatocellular / Q000473:pathology; D003460:Crystallization; D007150:Immunohistochemistry; D008113:Liver Neoplasms / Q000473:pathology; D008297:Male; D051381:Rats; D017208:Rats, Wistar; D012878:Skin Neoplasms / Q000276:immunology / Q000473:pathology* / Q000648:ultrastructure; D000515:alpha 1-Antitrypsin / Q000032:analysis* / Q000276:immunology
chemical_list: D000515:alpha 1-Antitrypsin