title: Gastric metastasis by primary lung adenocarcinoma.
abstract: The diagnosis of gastric metastasis from lung cancer is relatively rare in living patients. We describe a case of Type 4 tumor-like metastasis due to primary lung cancer diagnosed with immunohistochemical staining while the patient was alive. A 68-year-old man was admitted to our hospital because of epigastric pain. Gastrointestinal endoscopy revealed a Type 4 tumor and the histological examination showed poorly differentiated adenocarcinoma. His chest X-ray showed mass shadow in the right upper lung field. The resected specimens showed moderately differentiated adenocarcinoma., The diagnosis of gastric metastasis from lung cancer was made by immunohistochemical staining of the lung and gastric tumors which showed positive staining for Thyroid transcriptional factor-1. Diagnosis of gastric metastasis, especially Type 4 metastasis by lung cancer is difficult. However, immunohistochemical staining is very helpful for diagnosis of primary lung cancer metastasis at sites such as the gastrointestinal tract which are not normally prone to metastatis.
authors.affiliation: Ryota Okazaki, Kenichi Takeda, Takashi Sumikawa, Akira Yamasaki, Shingo Matsumoto, Eiji Shimizu, Division of Medical Oncology and Molecular Respirology, Department of Multidisciplinary Internal Medicine, Faculty of Medicine, Tottori University, 36-1 Nishi-machi, Yonago-shi, Tottori-ken 683-8504, Japan.
authors.forename: Ryota
authors.initials: R
authors.lastname: Okazaki
authors.forename: Hideyuki
authors.initials: H
authors.lastname: Ohtani
authors.forename: Kenichi
authors.initials: K
authors.lastname: Takeda
authors.forename: Takashi
authors.initials: T
authors.lastname: Sumikawa
authors.forename: Akira
authors.initials: A
authors.lastname: Yamasaki
authors.forename: Shingo
authors.initials: S
authors.lastname: Matsumoto
authors.forename: Eiji
authors.initials: E
authors.lastname: Shimizu