Stomach cancer is a disease in which cancer cells grow in the
stomach. Stomach cancer can develop in any part of the stomach
and spread to other organs through tumor growth, the
bloodstream, or the lymphatic system. There are five layers of
tissue in the stomach. The innermost layer is called the mucosa
and is where approximately 90% to 95% of stomach cancer begins.
This type of tumor is called an adenocarcinoma. Less common
stomach cancers include: - Lymphoma—a cancer of the immune
system; sometimes found in the stomach wall - Gastric stomal
tumors—tumors of the stomach wall - Carcinoid tumors—tumors of
the hormone-producing cells of the stomach It is believed that
stomach cancer takes several years to develop. Many precancerous
changes that rarely cause symptoms occur before stomach cancer
develops. This is why most cases of stomach cancer are
undetected until the later stages of the disease. Copyright ©
Nucleus Medical Media, Inc. The exact cause of stomach cancer is
not known. There are, however, several