The vast majority of stomach cancers arise from the glandular lining of the stomach and are called: adenocarcinomas. Some have a finite pre-cancer stage, and it is this stage that the Japanese screening programme is designed to pick up (as this stage is curable by surgery).
Although there are various descriptions that experts have given to the subtyping of the adenocarcinomas of the stomach, there has not overall been a good correlation between histological (i.e. down the microscope descriptions) and outlook for the patient. Molecular biological testing is now helping the pathologist who examines the biopsy to identify some more aggressive characteristics, which will impact on the patient’s outlook. It seems that the over-expression of the c-erb-B2 (HER-2) oncogene by the tumour cells is associated with aggressive tumour behaviour and the over-expression of the EGFR (epidermal growth factor receptor – which is encoded with in the erb-B1 oncogene ) may be related to worse prognosis.
Clearly the prediction of prognosis from molecular testing of the biopsy samples will be a developing area in this disease.