Cancer is one of the most deadly diseases which affect human beings. Cancer can affect different organs of the human body like eyes, colon, esophagus, etc. Stomach cancer happens when malignant (cancerous) cells build up in the lining of the stomach’s wall.

The stomach is a J-shaped organ which lies in the upper abdomen. It is a part of the digestive tract of human beings. The stomach’s wall is made of 3 layers of tissue: the mucosal layer (innermost layer), the muscularis layer (middle layer) and the serosal layer (outermost layer). There are 5 stages of gastric cancer:

Stage 0 or Carcinoma-in-situ (CIS):

Stage 0 is a very early stage of the cancer

. In this stage, unusual growth of cells is seen in the inner lining of the innermost layer (mucosa layer) of the stomach’s wall. These abnormal cells can further develop into cancerous cells and they can spread on to the surrounding tissues.

Stage 1:

In this stage, the cancer develops in the inner lining of the innermost layer (mucosa layer) of the stomach’s wall. Depending on the area where the cancerous cells have spread, this stage is divided into two: stage IA and stage IB.

 Stage IA: In this, the cancer spreads into the submucosa layer (the layer next to the mucosa) of the wall of the stomach.

 Stage IB: In stage IB, the cancer either spreads into the submucosa layer (the layer adjacent to the mucosa) and is also found in some lymph nodes around the tumor or spreads to the layer of muscles of the stomach’s wall.

Stage 2

: This stage is also divided into two, stage IIA and stage IIB, depending on the area where the cancerous cells have spread:

Stage 2A: In this stage, the cancer spreads either to the subserosa layer (next to serosa layer) of the stomach’s wall or to the muscular layer of the wall of the stomach along with 1 or 2 lymph nodes close to the tumor, or it spreads to the submucosa layer (next to mucosa) along with 3 to 6 lymph nodes around the tumor.

Stage 2B: In this, cancer spreads either to the serosa (outermost) layer of the stomach’s wall or to the muscular layer of the stomach’ wall along with 3 to 6 lymph nodes around the tumor; or spreads to the submucosa layer (next to the mucosa) along with 7 or more lymph nodes surrounding the tumor.

Stage 3:

This stage has 3 parts- IIIA, IIIB AND IIIC. In this stage, the cancerous cells spread to the nearby organs such as spleen, liver, pancreas, etc.

Stage 4:

This is the most advanced stage of the disease in which the cancer spreads to other parts of the body.