Oncologist-approved cancer information from the American Society of Clinical Oncology
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Pain: Causes and Diagnosis

This section has been reviewed and approved by the Cancer.Net Editorial Board, 5/2012


Pain is a common symptom in people with cancer. However, it may help to know that up to 95% of cancer pain can be treated successfully. Untreated pain can make other aspects of cancer seem worse, such as fatigue, weakness, shortness of breath, nausea, constipation, sleep disturbances, depression, anxiety, and mental confusion.

Not all people with cancer benefit from pain relief strategies because they don't share the symptoms with their health care team. Other people worry that pain medication is addictive or will make them sleepy or groggy. Your doctor or a pain specialist can help you find a medication that works for you and suggest other methods of pain relief in addition to medication.

Relieving side effects, also called symptom management, palliative care, or supportive care, is an important part of cancer care and treatment. Talk with your health care team about any symptoms of pain you may experience, including any new symptoms or a change in symptoms.


Pain can come from the tumor itself, may be a result of cancer treatment, or could be from causes not related to cancer. A good pain treatment plan will take care of pain from all causes.

The tumor. A tumor growing in an organ, such as the liver, may stretch part of the organ, and this stretching causes pain. If a tumor grows and spreads to the bones or other organs, it may put pressure on nerves and damage them, causing pain. Or, if a tumor spreads or grows around the spinal cord, it can cause a compression of the spinal cord, which eventually leads to severe pain or paralysis if not treated.

Surgery. It is normal to experience pain from cancer surgery. Most pain goes away after a while, but some people may have persistent pain for months or years from permanent damage to the nerves.

Radiation therapy. Pain may develop after radiation therapy and go away on its own. It can also develop months or years after treatment, especially after radiation therapy to the chest, breast, or spinal cord.

Chemotherapy. Some chemotherapy can cause pain along with numbness in the fingers and toes. Usually this pain goes away when treatment is finished, but sometimes the damage is permanent. Learn more about peripheral neuropathy.

Find out more about the side effects of surgery, radiation therapy, and chemotherapy.

Other causes. People with cancer can still have pain from other causes, like migraines, arthritis, or chronic low back pain. The treatment plan your doctors develop with you should also include these kinds of pain, because any pain decreases your quality of life.


You know your own pain best. To help your doctor better understand your pain, he or she may ask the following questions about your pain:

  • Where it hurts?
  • When the pain stops and starts?
  • How long it has been there?
  • How intense the pain is
  • What the pain feels like, in your own words

The doctor may also ask you to describe the pain using a scale from 1 to 10 or offer words that help describe the pain, such as burning, stabbing, or throbbing.

Management and treatment

There are variety of ways to manage and treat cancer pain, including medication and methods that don't use medication. Read managing and treating cancer pain, part I and part II for details.

More Information

ASCO Answers: Managing Pain

Managing Side Effects

Additional Resources

Oncology Nursing Society: The Cancer Journey: Pain

LIVESTRONG: Chronic Pain

Union for International Cancer Control: Treat the Pain

© 2005-2014 American Society of Clinical Oncology (ASCO). All rights reserved worldwide.

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