Published online Mar 15, 2015. doi: 10.4251/wjgo.v7.i3.12
Peer-review started: September 29, 2014
First decision: January 8, 2015
Revised: February 25, 2015
Accepted: March 5, 2015
Article in press: March 6, 2015
Published online: March 15, 2015
Processing time: 165 Days and 19.1 Hours
Gastric metastases from lung adenocarcinoma are rare. Because gastric metastasis grossly resembles advanced gastric cancer, it is difficult to diagnose gastric metastasis especially when the histology of the primary lung cancer is adenocarcinoma. We describe a case of gastric metastasis from primary lung adenocarcinoma mimicking Borrmann type IV primary gastric cancer. A 68-year-old man with known lung adenocarcinoma with multiple bone metastases had been experiencing progressive epigastric pain and dyspepsia over one year. Esophagogastroduodenoscopy revealed linitis plastica-like lesions in the fundus of the stomach. Pathologic examination revealed a moderately differentiated adenocarcinoma with submucosal infiltration. Positive immunohistochemical staining for thyroid transcription factor-1 (TTF-1) and napsin A (Nap-A) confirmed that the metastasis was pulmonary in origin. The patient had been treated with palliative chemotherapy for the lung cancer and had lived for over fifteen months after the diagnosis of gastric metastasis. Clinicians should be aware of the possibility of gastric metastasis in patients with primary lung adenocarcinoma, and additional immunohistochemical staining for Nap-A as well as TTF-1 may help in differentiating its origin.
Core tip: This report describes the rare case of a 68-year-old patient with gastric metastasis from primary lung adenocarcinoma mimicking Borrmann type IV primary gastric cancer. When gastric carcinoma is suspected in patients with primary lung adenocarcinoma, a differential diagnosis of primary gastric cancer and gastric metastasis can be done through special immunohistochemical staining with napsin-A and thyroid transcription factor-1, especially when the biopsy results are ambiguous by histology alone.