Published online Oct 7, 2015. doi: 10.3748/wjg.v21.i37.10502
Peer-review started: February 27, 2015
First decision: April 14, 2015
Revised: April 20, 2015
Accepted: August 25, 2015
Article in press: August 25, 2015
Published online: October 7, 2015
Processing time: 213 Days and 13.4 Hours
A substantial portion of patients with newly diagnosed gastric cancer has distant metastases (M1 disease). These patients have a very poor prognosis and it is generally accepted that they should be treated with noncurative intent. Because it dramatically changes prognosis and treatment plans, it is very important to diagnose distant metastases. In this article, the definition, pathways, incidence and sites of distant metastases in gastric cancer are described. Subsequently, the current performance of imaging in detecting distant metastases in newly diagnosed gastric cancer is outlined and future prospects are discussed.
Core tip: Computed tomography is currently the primary imaging modality for M staging. Evaluation of ascites by endoscopic ultrasonography is useful because it has a high probability for the presence of peritoneal metastases. Staging laparoscopy is still necessary in patients with locally advanced disease with no definite evidence of peritoneal metastases at imaging. The roles of 18F-fluoro-2-deoxy-D-glucose positron emission tomography and magnetic resonance imaging need to be further explored. New imaging techniques and strategies are needed to improve M staging.