By Yvette Brazier: MedicalNewsToday.com:
Drinking alcohol, eating processed meat and being overweight increase the risk of developing stomach cancers, according to a major new scientific report released by the American Institute for Cancer Research and the World Cancer Research Fund.
The Continuous Update Project (CUP) report was led by the American Institute for Cancer Research (AICR) and the World Cancer Research Fund (WCRF).
Scientists systematically gathered and analyzed data relating to stomach cancer, after which a panel of leading international experts evaluated the results independently. Worldwide, there were 952,000 cases of stomach cancer in 2012, or 7% of all new cancer cases.
Stomach cancer is the third most common cause of cancer death. It affects men twice as much as women, and it is more common among older people, with the average age of diagnosis in the US being 72 years.
In Europe and the US, the survival rate is 25-28%, rising to 63% if it is diagnosed early. But symptoms may not appear until the later stages, and some 70% of cases worldwide are diagnosed late, leading to a lower survival rate. Eastern Asia and China are particularly affected.
Classification of stomach cancer depends on where the tumor develops. Cardia stomach cancer occurs at the top of the stomach, near the esophagus; non-cardia cancer occurs anywhere else in the stomach.
Non-cardia stomach cancer is more prevalent, and especially in Asia, but the rates are declining. This may be due to a decrease in Helicobacter pylori (H. pylori) infection, and because more people are using refrigeration, rather than salt, to preserve food.
However, cardia stomach cancer is now more frequent in the US and the UK, and the trend is growing.
Previous findings have suggested that smoking is responsible for 11% of cases of stomach cancer worldwide.
Infection by H. pylori infection is known to cause non-cardia stomach cancer, and investigations are under way into a link with Epstein-Barr virus.
Industrial chemical exposure and workplace exposure to dust and high temperature have also been implicated. People who operate food machines and those employed in rubber manufacturing, wood or metal processing, chromium production and coal mining are thought to be at greater risk.
The current study highlights the impact of certain lifestyle factors on the risk of developing stomach cancer. It involved 89 meta-analyses and data for 17.5 million adults, 77,000 of whom had stomach cancers.