What is Cancer?

The body is made up of many cells that have specific functions in the body. Cancer is a disease that is caused by an uncontrolled division of abnormal cells in any part of the body. These cancer cells divide and use up cell resources, this causes normal cells to starve and die. When normal cells die, cell function is disrupted. Abnormal cell division can lead to the formation of a tumor, which is a collection of cells. A malignant tumor is a tumor that has the capacity to invade surrounding tissue and metastasize, or spread, throughout the body.  
 

What is Stomach Cancer?

Stomach cancer, also known as gastric cancer, is cancer that originates in the stomach. The stomach is a sac-like organ that functions to process and store food. During digestion, the stomach breaks down food, which is slowly released into the small intestine where nutrients can be absorbed. 


Types of Stomach Cancer

There are multiple types of stomach cancer. The type of stomach cancer is important because different treatments are available depending on the cancer type. Often a pathology sample is needed to determine the type.

Adenocarcinoma is the most common form of stomach cancer that occurs in 95% of all cases. In adenocarcinoma, cancer cells originate in gland cells that secrete gastric juices (stomach acid) inside the inner stomach lining (mucosa). There are two types of adenocarcinoma with even more subtypes.  Diffuse Adenocarcinoma is most common in younger people, it includes mucinous, infiltrative and signet ring carcinoma. Intestinal adenocarcinoma is most common in older people and it includes papillary, tubular and mucinous types of cancer. Intestinal ademocarcinoma forms a tumor mass, which is a collection of cancer cells. Whereas in diffuse adenocarcinoma, there is no tumor mass and cancer cells are found scattered in many places of the stomach.

 The remainder of stomach cancer types are:
Adenosquamous Carcinoma: cancer cells originate in the space between gland cells
Gastrointestinal Stromal Tumors (GIST): tumor originating in the connective tissue of the gastrointestinal tract
Neuroendocrine Carcinoma: tumor makes hormones
Gastric Lymphoma: cancer originating in the lymph nodes