Fatigue and other symptoms typically arise with infections, too.
Yet fever symptoms are associated with specific types of cancer,leukemiaandlymphomaamong them.
This article defines what FUO is and some of its possible causes.
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It details why fever can be anearly symptomof leukemia and other cancers.
FUO doesn’t automatically indicate cancer.
There are more than 200 possible diagnoses associated with FUO, some of them quite rare.
In up to 50% of FUO cases, the cause of fever is never found.
Infections That Cause Fever
Many types of infections can lead to fever of unexplained origin.
Conditions may include:
Fever associated with an infection remains the leading cause of FUO.
Cancers That Cause Fever
Several different types of cancer may include FUO as a symptom.
However, a number of other health conditions may begin with infection and/or inflammation.
They also may include FUO as a symptom.
In most cases, the fever goes away within 72 hours if you stop taking the drug.
These include fevers, unintentional weight loss, and drenching night sweats.
These symptoms suggest a more aggressive and rapidly growing cancer.
Why Do People Get Fevers With Cancer?
The answer may depend on the throw in of cancer.
It’s far more likely that fever is because of the flu or another uncomplicated infection.
Once the infection has resolved, the fever will go away too.
That said, fever is a common symptom in some types of cancer, including leukemia and lymphoma.
These cancers of the blood are known to cause a fever in their early stages.
A Word From Verywell
Most FUOs will resolve on their own once the underlying cause is addressed.
That said, don’t ignore an unexplained fever, especially one that recurs.
It may be an important clue about a serious health issue.
These disorders are typically not fatal but must be managed across a lifetime.
Pel-Ebstein is a fever that cycles every seven to 10 days or so.
It’s not common, but a Pel-Ebstein fever pattern may be a symptom ofHodgkin lymphoma.
Fever due to cancer often will stop when the cancer is treated.
However, treatment itself (especially chemotherapy) may cause fever too.
This is likely related to infection and considered a medical emergency your healthcare provider needs to address.
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