title: Early gastric cancer superimposed on infestation of an Anisakis-like larva: a case report.
abstract: This report describes a 73-year-old male with early gastric cancer (type IIc) superimposed on infestation of a parasitic larva. Eosinophilic granulomas surrounding a dead worm were seen in the submucosa just beneath the intramucosal tubular adenocarcinomatous lesion measuring 1 X 1cm at the anterior wall in the acid-secreting area. The cancer cells showed lowered and altered mucin production in comparison with the surrounding non-cancerous fundic mucosa. The parasite was identified as an Anisakis-like larva by the presence of typical lateral chords. An immunohistochemical examination revealed that the cancer cells were more strongly positive for IgA and secretory component than the surrounding non-cancerous mucosa, and that IgG, IgA and IgM were detected in plasma cells around the granulomas but IgE and IgD were not. The possibility that the Anisakis-like larva preferentially infested the cancerous mucosa because of the change in mucin, local defect in acid secretion and/or other structural alterations in the area is discussed.
mesh_terms: D000230:Adenocarcinoma / Q000150:complications / Q000473:pathology*; D000368:Aged; D001199:Ascaridoidea; D005753:Gastric Mucosa / Q000473:pathology; D006801:Humans; D007136:Immunoglobulins / Q000032:analysis; D007814:Larva; D008297:Male; D009349:Nematode Infections / Q000150:complications / Q000276:immunology / Q000473:pathology*; D013274:Stomach Neoplasms / Q000150:complications / Q000473:pathology*
chemical_list: D007136:Immunoglobulins