Many people become confused over the definitions of a primary vs secondary or second cancer.
Primary cancer is defined as the original site (organ or tissue) where cancer began.
For example, cancer starting in the lungs is called primarylung cancer.
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Conversely, a person may have primary lung cancer and second primary brain cancer that is unrelated.
In this case, the cancerous cells in the brain would be brain cells and not lung cells.
For 3 out of every hundred people with cancer, the primary site of cancer isn’t found.
The reason is often because a tumor is very “undifferentiated.
“Cancer cells may resemble normal cells, sometimes making them relatively indistinguishable under a microscope.
Cancers do not always have a primary site.
An example of this is lymphoma.
Take time to learn about your cancer.
Ask a lot of questions.
If the answers are still unclear, ask again.
And, don’t hesitate to request a second opinion before making any decisions.
The distinction between primary and secondary cancer can make a significant difference in treatment options and approaches.
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American Cancer Society.What is a cancer of unknown primary?
American Cancer Society.If you have cancer of unknown primary.
Division of Cancer Epidemiology and Genetics.Second primary cancers.
