Mixed mucinous-type and non-mucinous-type adenocarcinoma of the lung: Immunohistochemical examination and K-ras gene mutation

Arafumi Maeshima, Michiie Sakamoto, Setsuo Hirohashi

Research output: Contribution to journalArticle

26 Citations (Scopus)


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.

Original languageEnglish
Pages (from-to)598-603
Number of pages6
JournalVirchows Archiv
Issue number6
Publication statusPublished - 2002 Aug 5



  • K-ras gene
  • Lung adenocarcinoma
  • Lysozyme
  • Mucinous type
  • Non-mucinous type

ASJC Scopus subject areas

  • Pathology and Forensic Medicine
  • Molecular Biology
  • Cell Biology

Cite this