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Cancer Treatment Principles


The Manual's Editorial Staff

Last full review/revision Jul 2021| Content last modified Jul 2021
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What are the goals of cancer treatment?

The main goal is to get rid of your cancer. This can happen with one type of treatment (such as surgery) or a mix of treatments, such as surgery and chemotherapy (medicine that destroys cancer cells) and radiation therapy.

If it isn’t possible to remove your cancer, doctors will try to shrink it, make you more comfortable, and lessen your symptoms to help you feel better.

Treating cancer is complex, and doctors and other healthcare professionals work together as a team. Your team may include primary care doctors, specialists, surgeons, physician assistants, radiation therapists, nurses, social workers, and pharmacists.

Your doctors will choose the type of treatment (called a treatment protocol) that’s best for your cancer.

How do doctors choose the right treatment for your cancer?

Doctors decide on the best treatment for your cancer based on:

  • The chance of a cure (your cancer goes away and doesn’t come back)

  • The chance of the longest, most comfortable life

  • How well the treatment will lessen your symptoms

  • Side effects of treatment

  • Your wishes for treatment

Talk with your doctor about the pros and cons of different treatments.

Treatment protocols are standard methods developed by doctors to treat certain types of cancer. These plans have been tested carefully in research studies called clinical trials. In clinical trials, doctors compare new drugs and treatments with standard treatments to help tell whether the new treatments work better. Many people with cancer are offered the chance to be in a clinical trial. Talk with your doctor about the advantages and disadvantages of being in a trial.

How do doctors tell if the treatment is working?

Doctors will check to see how well your treatment is working to fight cancer. During your treatment, doctors may:

  • Do scans (such as CT scans) to see if your tumors have shrunk

  • Do blood tests to check your levels of tumor antigens (called tumor markers for certain cancers) in your blood

If treatment works on your cancer, you may have:

  • Remission—your cancer disappears completely

  • A partial response—your tumor shrinks to less than half its previous size, which can give you fewer symptoms and lengthen your life

  • Relapse—your cancer completely disappears but returns later

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