About rare and less common cancers

What are rare and less common cancers?

A rare and less common (RLC) cancer is a type of cancer that affects a small number of people. An RLC cancer may take longer and be more difficult to diagnose than other types of cancer. It may also be found at a late stage (advanced).

Breast, bowel, prostate and lung cancer are examples of common cancers. Many people are diagnosed with these types of cancers.

Small bowel and gallbladder cancer are examples of rare or less common cancers. Few people are diagnosed with these types of cancers.

A cancer may be considered an RLC cancer when it:

• is a subtype of a more common cancer (e.g. lymphoma is common; T-cell lymphoma is rare)
• is a common cancer in an unusual part of the body (e.g. melanoma is common, but melanoma found in the eye, called ocular melanoma, is rare)
• is in a part of the body where it is unusual to find cancer (e.g. the bones)
• started in a different type of cell than usual
• is more common to find this cancer type in the opposite sex (e.g. breast cancer in males)
• is found in a person younger than expected (e.g. prostate cancer in someone under 40).

How many Australians have a rare or less common cancer?

A rare cancer means fewer than 6 out of 100,000 people who are diagnosed with cancer have this type. A cancer is less common if 6–12 out of 100,000 people are diagnosed with this type.

There are a large number of different types of rare or less common cancers. Although only a small number of people are diagnosed with each RLC cancer type (e.g. small bowel, gallbladder), together, they all add up to a large number.

Each year, it’s estimated about 52,000 Australians are diagnosed with a cancer that is considered to be rare or less common. Almost 1 in 3 people diagnosed with cancer will have an RLC cancer.

The number of people diagnosed with an RLC cancer is increasing. While the incidence of certain RLC cancer types may be on the rise, this overall increase in numbers may also be partly due to:

• improvements in diagnosing different types of cancer
• advances in testing (including genetic testing)
• early detection thanks to more accurate cancer screening.

Rare and less common cancer in children

Any cancer affecting children and teenagers is considered rare. This is because it is unusual for younger people to have cancer. The same type of cancer found in an adult may not be considered rare. For more information about children and cancer, visit Cancer Australia's Children's Cancer pages.