Tumours of the stomach

Gastric tumours are either epithelial or stromal in origin. Benign tumours are rare with the majority being malignant and mostly adenocarcinomas. Gastric lymphomas, gastrointestinal stromal tumours (GISTs) and gastric carcinoid are less common and have variable cancer biology. Gastric adenocarcinoma is the eighth-commonest cancer in the UK. Proximally situated cancers are most frequent. It is characterized by late presentation with 80% of patients presenting with locally advanced or distant metastatic disease. Recognition of early gastric cancer remains a challenge in low-incidence areas. Improvements in imaging techniques have allowed more individualized, tailored and stage-related treatments. Outcome in localized cancers has improved with multi-modality therapies yet overall survival remains poor. Gastric lymphomas are the commonest gastrointestinal tract lymphoma and many arise from mucosa-associated lymphoid tissue. These are low grade but may progress to high grade lymphomas. GISTs usually have a benign biology although a third can be locally invasive and metastasize. The tumour cells express a growth factor receptor with tyrosine kinase activity, which is susceptible to targeted therapy.