A fever is a body temperature that is higher than normal. But, a normal temperature in one person might be different from a normal temperature in another person. This is why it's important to find out what your cancer care team thinks might be a fever for you. They will tell you what temperature you should consider higher than normal.
Fever is usually caused by an infection. Other causes of fever may include inflammation, medication reactions, or tumor growth. Sometimes, the cause might not be known or easy to find. In an infection, the fever is a result of your body trying to fight invading germs. Fever is an important natural defense against germs.
People getting cancer treatments have a higher risk for infections because cancer treatment can cause neutropenia, a condition in which you have fewer white blood cells than normal to help fight infections.
To know if you have a fever, you will need to take your temperature. To take your temperature, you will need a thermometer. Ask your cancer care team what kind of thermometer is best. You can buy an easy-to-use oral thermometer (one made to take your temperature by mouth) at any drugstore so you can check to see if you have a fever. If you have any of the following symptoms, it is important that you take your temperature:
You may have heard your cancer care team talk about neutropenic fever. In patients with neutropenia, fever may often be the first and sometimes only sign of infection. If this happens, your cancer care team will assess you and likely start treatment for infection right away. Treatment of a patient with neutropenic fever usually means starting the patient on antibiotics before they take tests that will confirm an infection.
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Our team is made up of doctors and oncology certified nurses with deep knowledge of cancer care as well as journalists, editors, and translators with extensive experience in medical writing.
Freifeld AG, Kaul DR. Infection in the patient With cancer. In Niederhuber JE, Armitage JO, Kastan MB, Doroshow JH, Tepper JE, eds. Abeloff’s Clinical Oncology. 6th ed. Philadelphia, PA: Elsevier; 2020:544-562
National Comprehensive Cancer Network (NCCN). Prevention and treatment of cancer-related infections. 2018. Version 1.2019. Accessed at https://www.nccn.org/professionals/physician_gls/PDF/infections.pdf on August 27, 2019.
Palmore TN, Parta M, Cuellar-Rodriguez J, Gea-Banacloche JC. Infections in the cancer patient. In DeVita VT, Lawrence TS, Rosenberg SA, eds. DeVita, Hellman, and Rosenberg’s Cancer: Principles and Practice of Oncology. 11th ed. Philadelphia, PA: Lippincott Williams & Wilkins; 2019:2037-2068.
Last Revised: February 1, 2020
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