Molecular classification of gastric cancer

Gastric cancer is the world’s third leading cause of cancer mortality and the most common cancer diagnosed in men in Japan (1). Clinical work-up of gastric cancer relies in part on imaging modalities, including endoscopic ultrasound and CT/PET, and pathologic analysis of tumor biopsies. Gastric cancer is clinically classified as early or advanced stage, with early disease confined to mucosa/submucosa and advanced carcinoma invading into muscularis propria and beyond (2).