title: Mixed mucinous-type and non-mucinous-type adenocarcinoma of the lung: immunohistochemical examination and K- ras gene mutation.
abstract: Mucinous-type adenocarcinoma and non-mucinous-type adenocarcinoma are known to be the representative histological subtypes of bronchioloalveolar carcinoma. Mucinous-type adenocarcinoma is also known to carry abnormalities of the K- ras gene at high frequency. However, the mixed subtype of the both mucinous-type and non-mucinous-type adenocarcinoma (mixed-type) has not been analyzed in detail, although its existence has been reported in a few papers. In this study we carried out immunohistochemical and molecular biological analyses of 15 examples of the mixed-type, in comparison with 11 cases of mucinous-type and 21 cases of non-mucinous-type adenocarcinoma. Immunohistochemically, lysozyme - one of the specific markers of mucinous-type adenocarcinoma - was not stained in the mucinous component of the mixed-type. K- ras gene mutations were detected only in mucinous-type (73%) and non-mucinous-type (10%) adenocarcinomas and not in either the mucinous or non-mucinous component of the mixed-type (0%). Therefore, although mixed-type adenocarcinomas consist of tumor cells showing both mucinous and non-mucinous morphology, the mucinous component of this type differs from mucinous-type adenocarcinoma in terms of immunohistochemical features and K- ras gene alteration.
authors.affiliation: Pathology Division, National Cancer Center Research Institute, 5-1-1, Tsukiji, Chuo-ku, Tokyo 104-0045, Japan.
authors.forename: Arafumi
authors.initials: A
authors.lastname: Maeshima
authors.forename: Michiie
authors.initials: M
authors.lastname: Sakamoto
authors.forename: Setsuo
authors.initials: S
authors.lastname: Hirohashi
mesh_terms: D002288:Adenocarcinoma, Mucinous / Q000145:classification / Q000235:genetics* / Q000378:metabolism / Q000473:pathology; D000368:Aged; D000369:Aged, 80 and over; D005260:Female; D011905:Genes, ras; D006801:Humans; D007150:Immunohistochemistry; D008175:Lung Neoplasms / Q000145:classification / Q000235:genetics* / Q000378:metabolism / Q000473:pathology; D008297:Male; D008875:Middle Aged; D009113:Muramidase / Q000378:metabolism; D009154:Mutation
chemical_list: D009113:Muramidase