And while many cancers recur in the first five years, some can recur decades later.
Why do some cancers come back, and how does this happen?
Importance of Knowing Why Cancers Recur
Often, cancer recurrence is metastatic.
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An initial cancer that was stage 1 or stage 2 can recur in stage 4 with metastases.
More than 90% of cancer deaths occur due to metastases.
Cancer treatments are intended to prevent cancer cells from growing or persisting in the body.
This is why adjuvant chemotherapy is part of the treatment for early-stage breast and lung cancers.
Why Do Some Cancers Come Back?
Sometimes, people who were successfully treated for cancer are diagnosed with a recurrence.
This does not mean that their treatment was incorrect or unsuccessful.
Rather, it is important to understand that some cancers are more likely to return than others.
It only takes a fewcancer cellsleft over after treatment for that cancer to grow again.
These undetectable cells are referred to asmicrometastases.
Surgery and radiation therapy are considered local treatments.
As such, they do not treat cancer cells that have traveled beyond the treatment region.
In addition, radiation therapy may not kill all cancer cells.
Radiation works by damaging DNA in both cancer cells and normal cells.
Just as normal cells may recover following radiation, some cancer cells may recover as well.
Chemotherapy
Chemotherapy, unlike surgery and radiation therapy, is considered a systemic therapy.
So why wouldn’t chemotherapy kill all cancer cells in the body?
A strong immune system can help keep cancer cells dormant.
Cancer does not always recur in the same area of the body as the original tumor.
Some people can experience recurrence in different organs or body systems.
Which Cancers Recur?
Some cancers are more likely to recur than others.
Treating Recurrent Cancer
Some cancers can be more difficult to treat when they recur.
But that does not mean your cancer cannot be treated a second time.
Some forms of cancer, such astesticular cancer, may still be curable even after they recur.
Some people may question whether they could have prevented the recurrence, but often that is not the case.
Coping with recurrent cancer isn’t just about the medical aspects.
Ovarian cancer has a recurrence rate of approximately 85%.
Which cancers have the lowest recurrence rates?
Cancers that have relatively low recurrence rates include estrogen receptor-positive breast cancer, kidney cancer, and Hodgkin lymphoma.
How is recurrence different from a second cancer?
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