title: Pancreatoblastoma. A case report with special emphasis on squamoid corpuscles with optically clear nuclei rich in biotin.
abstract: BACKGROUND
  Pancreatoblastoma (PBL) is a rare neoplasm that generally occurs in the pediatric age group and shows unique histopathology, including squamoid corpuscles that may contain tumor cells with optically clear nuclei (OCN) rich in biotin. In the English-language literature there have been two reports on the cytology of PBL, but neither of them refers to the cytologic features of squamoid corpuscles.
  
  
  METHODS
  A 3-year-old boy with nausea and general fatigue was referred to our center. Imaging studies showed an approximately 7.5-cm, left-sided abdominal mass and multiple metastases in the lung. The abdominal mass was biopsied, and its histology showed solid cellular nests with occasional acinar differentiation and squamoid corpuscles. Imprint cytology of the biopsied sample displayed cellular epithelial nests with focal acinar structures and foci composed of larger cells with a low nuclear/cytoplasmic ratio. These foci contained a few tumor cells with biotin-rich OCN and were determined to be squamoid corpuscles.
  
  
  CONCLUSIONS
  Detection of occasional squamoid corpuscles with biotin-rich OCN can be useful in making a diagnosis of PBL on cytologic samples.
authors.affiliation: Division of Clinical Laboratory, Kanagawa Children's Medical Center, Mutsukawa 2-138-4, Minami-ku, Yokohama, 232-8555, Japan.
authors.forename: Yukari
authors.initials: Y
authors.lastname: Hasegawa
authors.forename: Yuji
authors.initials: Y
authors.lastname: Ishida
authors.forename: Keisuke
authors.initials: K
authors.lastname: Kato
authors.forename: Rieko
authors.initials: R
authors.lastname: Ijiri
authors.forename: Tetsumi
authors.initials: T
authors.lastname: Miyake
authors.forename: Shigeo
authors.initials: S
authors.lastname: Nishimata
authors.forename: Takako
authors.initials: T
authors.lastname: Watanabe
authors.forename: Ikuko
authors.initials: I
authors.lastname: Namba
authors.forename: Yoko
authors.initials: Y
authors.lastname: Hayabuchi
authors.forename: Hisato
authors.initials: H
authors.lastname: Kigasawa
authors.forename: Yukichi
authors.initials: Y
authors.lastname: Tanaka
mesh_terms: D014408:Biomarkers, Tumor; D001710:Biotin / Q000378:metabolism; D002467:Cell Nucleus / Q000378:metabolism / Q000473:pathology; D002675:Child, Preschool; D004847:Epithelial Cells / Q000378:metabolism / Q000473:pathology*; D006801:Humans; D002479:Inclusion Bodies / Q000473:pathology; D008297:Male; D009373:Neoplasms, Germ Cell and Embryonal / Q000378:metabolism / Q000473:pathology*; D010179:Pancreas / Q000378:metabolism / Q000473:pathology*; D010190:Pancreatic Neoplasms / Q000378:metabolism / Q000473:pathology*; D013234:Stem Cells / Q000378:metabolism / Q000473:pathology*
chemical_list: D014408:Biomarkers, Tumor; D001710:Biotin