title: Novel epitheliomesenchymal biphasic stomach tumour (gastroblastoma) in a 9-year-old: morphological, ultrastructural and immunohistochemical findings.
abstract: Gastroblastoma is a rare gastric epitheliomesenchymal biphasic tumour composed of spindle and epithelial cells, reported by Miettinen et al in a series of three cases in 2009. All those cases arose in stomachs of young adults. Neither the epithelial nor the mesenchymal component displayed sufficient atypia to diagnose a carcinosarcoma or other malignancy. On immunohistochemistry, the epithelial component expressed cytokeratin, and the mesenchymal component was positive for vimentin and CD10. Miettinen et al designated these neoplasms as gastroblastomas based on their similarities with other childhood blastomas such as pleuropulmonary blastoma and nephroblastoma. This report describes a probable fourth case of this unique type of neoplasm. The present case arose in the gastric antrum of a 9-year-old boy. While similarities were evident with the other cases, there were some differences. The epithelial component was more predominant and showed more mature morphology. Immunohistochemically, the epithelial component showed immunolabelling for c-KIT and CD56. The mesenchymal component was only focally positive for CD10. Ultrastructually, desmosomes and microvilli were found supporting a truly epithelial lesion.
authors.affiliation: Department of Pathology, Pusan National University School of Medicine, Yang-san, Korea.
authors.forename: Dong Hoon
authors.initials: DH
authors.lastname: Shin
authors.forename: Jung Hee
authors.initials: JH
authors.lastname: Lee
authors.forename: Hyun Jeong
authors.initials: HJ
authors.lastname: Kang
authors.forename: Kyung Un
authors.initials: KU
authors.lastname: Choi
authors.forename: Jee Yeon
authors.initials: JY
authors.lastname: Kim
authors.forename: Do Youn
authors.initials: DY
authors.lastname: Park
authors.forename: Chang Hun
authors.initials: CH
authors.lastname: Lee
authors.forename: Mee Young
authors.initials: MY
authors.lastname: Sol
authors.forename: Jae Hong
authors.initials: JH
authors.lastname: Park
authors.forename: Hae Young
authors.initials: HY
authors.lastname: Kim
authors.forename: Elizabeth
authors.initials: E
authors.lastname: Montgomery
mesh_terms: D002277:Carcinoma / Q000235:genetics / Q000648:ultrastructure*; D002648:Child; D006801:Humans; D008297:Male; D008637:Mesenchymoma / Q000235:genetics / Q000648:ultrastructure; D009154:Mutation; D018193:Neoplasms, Complex and Mixed / Q000235:genetics / Q000648:ultrastructure*; D019009:Proto-Oncogene Proteins c-kit / Q000235:genetics / Q000378:metabolism; D013274:Stomach Neoplasms / Q000235:genetics / Q000378:metabolism / Q000648:ultrastructure*
chemical_list: D019009:Proto-Oncogene Proteins c-kit