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How does cancer cause signs and symptoms?

The quick brown fox jumped over the lazy dog. Box content[/su_box]Cancer is a group of diseases that can cause almost any sign or symptom. The signs and symptoms will depend on where the cancer is, how big it is, and how much it affects the organs or tissues. If a cancer has spread (metastasized), signs or symptoms may appear in different parts of the body.

As a cancer grows, it can begin to push on nearby organs, blood vessels, and nerves. This pressure causes some of the signs and symptoms of cancer. If the cancer is in a critical area, such as certain parts of the brain, even the smallest tumour can cause symptoms.

But sometimes cancer starts in places where it won’t cause any signs or symptoms until it has grown quite large. Cancers of the pancreas, for example, usually don’t cause symptoms until they grow large enough to press on nearby nerves or organs. Others may grow around the bile duct and block the flow of bile. This causes the eyes and skin to look yellow (jaundice). By the time a pancreatic cancer causes signs or symptoms like these, it’s usually in an advanced stage. This means it has grown and spread beyond the place it started – the pancreas.

A cancer may also cause symptoms like fever, extreme tiredness (fatigue), or weight loss. This may be because cancer cells use up much of the body’s energy supply, or they may release substances that change the way the body makes energy from food. Cancer can also cause the immune system to react in ways that produce these signs and symptoms.

— Read more from The American Cancer Society.

General cancer warning signs

Cancer warning signs (English)
CANSA Waarskuwingstekens vir Kanker
Waarskuwingstekens vir Kanker (Afrikaans)

There are many different types of cancer, and they can affect all parts of the body, and in many different ways. There is no single warning sign for cancer, and many of the signs may be similar to other problems. So the general advice would be to follow up any health issue in the normal way. However, if the condition does not improve within a reasonable time, or even gets worse, then a follow-up with your doctor or clinic is advised.

Here are some useful resources which can help:

CANSA: Cancer Warning Signs, or download infographic in both English and Afrikaans.

American Cancer Society: Signs and Symptoms of Cancer

And here’s a warning about cancer warning pages on the web or social media: Preferably always consult reputable national or international websites. There are far too many dubious sources which may contain some good advice, but generally this is mixed in with ulterior motives, such as selling particular products which may or may not be useful in fighting cancer.

 

What Are the Differences Between Cancers in Adults and Children?

The types of cancers that develop in children are often different from the types that develop in adults. Unlike many cancers in adults, childhood cancers are not strongly linked to lifestyle or environmental risk factors. Only a small number of childhood cancers are caused by DNA changes that are passed from parents to their child.

Some cancers become more prevalent with age, and therefore do not normally affect children. EG: Prostate cancer.

With some exceptions, childhood cancers tend to respond better to certain treatments. Children might seem to do better with cancer treatments than adults because they usually do not have other health problems that can get worse with cancer treatment. On the other hand, children (especially very young children) are more likely to be affected by radiation therapy if it is needed as part of treatment. Both chemo, radiation therapy, and other cancer treatments also can cause long-term side effects, so children who have had cancer will need careful follow-up for the rest of their lives.

Here are some resources which focus specifically on childhood cancer:

CHOC: Saint Siluan’s Early Warning Signs of Childhood Cancer

CANSA: Red Flags for Childhood Cancer

American Cancer Society: Finding Cancers in Children

 

Some Useful Training Materials

 

Return to main Cancer Resources page

Page last updated: October 2018