What is stomach cancer?
Stomach cancer develops when cells in any part of the stomach grow and divide in an abnormal way. Tumours can begin anywhere in the stomach, although most start in the stomach’s inner layer (mucosa). This type of cancer is called adenocarcinoma of the stomach (also known as gastric cancer). If it is not found and treated early, stomach cancer can spread to nearby lymph nodes or to other parts of the body, such as the liver and lungs as a secondary or metastatic cancer. It may also spread to the lining of the wall of the abdomen (peritoneum). Rarely, it can grow through the stomach wall into nearby organs such as the pancreas and bowel.
You can access further information about stomach cancer, including risk factors, symptoms, diagnosis and treatment from Cancer Council Victoria. You can also call our trusted cancer nurses on 13 11 20 for support and to learn about our range of services for people affected by cancer.
The Victorian Cancer Registry also operates an interactive web portal, Data Explorer, which provides more trends and statistics than published here.
How common is stomach cancer?
In 2022, 671 Victorians were diagnosed with stomach cancer. Of these, there were 413 males and 258 females, representing 61.5% and 38.5% of the total Victorian stomach cancer diagnoses, respectively. Currently, stomach cancer is diagnosed at a rate of 6.8 per 100,000 males and 3.8 per 100,000 females. The median age at diagnosis of stomach cancer is 70 years in males and 73 in females (Figure 1 & 2). Accounting for 1.8% of all cancers diagnosed and 3.3% of all cancer-related deaths in 2022, stomach cancer was the 15th most commonly diagnosed cancer and the 9th most common cause of cancer-related deaths in Victoria.
Trends in stomach cancer over time
Figure 3 shows that for males between 1982 to 2007 the incidence of stomach cancer declined by an average of 2.4% per year, and between 2007 to 2022 incidence declined by an average of 0.9% per year.
For females between 1982 to 2014 the incidence of stomach cancer declined by an average of 1.8% per year, and between 2014 to 2022 incidence stabilised.
For males between 1982 to 2001 the mortality of stomach cancer declined by an average of 3.7% per year, and between 2001 to 2022 mortality declined by an average of 1.3% per year.
For females between 1982 to 2022 the incidence of stomach cancer declined by an average of 2.5% per year.
Stomach cancer morphology
Figure 4 provides a summary of the different types of cells (morphology) which have caused stomach cancers among all cases. Most stomach cancer tumours, 82.6%, present as Adenocarcinoma tumours.
Geographical variance in stomach cancer by local government area
Figure 5 demonstrates variation in age-standardised incidence rates of stomach cancer, by local government areas. Darker shading indicates areas with higher rates of stomach cancer.
Stomach cancer in people born overseas
Figure 6 shows the age standardised incidence rates of stomach cancers in Australian-born Victorians compared to other major migrant groups, over the five-year period 2017 to 2021. The highest age standardised incidence rate for stomach cancers was 12 for males born in the South and Central America region and the lowest rate of 2.6 was observed in males born in the North America region. The highest age standardised incidence rate of stomach cancers was 8.9 for females born in the South and Central America region and the lowest rate of 2.8 was observed in females born in the Australia and New Zealand region.
Stomach cancer five-year relative survival
Figure 7 shows the change in 5-year survival for stomach cancer, and the 5-year survival trend for all cancers over the same time period. It demonstrates that five-year relative survival has increased for stomach cancer between 1982-1986 and 2017-2021 from 19% to 35%.
