Cancer Q&A: What Is Cancer Of An Unknown Primary?

Cancer Q&A: What Is Cancer Of An Unknown Primary?

The following information is provided by the Cancer Services of Greater Baton Rouge and was published by The Advocate.

QUESTION: I know someone who says they have a cancer of unknown primary. What does that mean?

ANSWER: Cancer of an unknown primary is cancer that has been found in the body but doctors cannot determine where the cancer started. This means that the cancer has spread (metastasized) and has been detected, but doctors cannot pinpoint exactly what type of cancer it is.

The place of origin for cancer is important because it is the main determination of what type of treatment is used. According to the National Cancer Institute, only about 2 to 4 oercebt of cancers are CUPs.

To try to determine the original site, doctors may perform a biopsy (the removal of cells or tissues for examination), perform a physical exam, order x-rays, order blood, urine and stool tests and/or ask for a complete history of the patient. If the tests do not show any determinant factor of where it originally began growing, then the cancer is called CUP.

To treat CUP, doctors have to take the following factors into consideration: cell type, to determine the most probable primary site; location of metastasis; patient’s general status; risk factors, like tobacco or alcohol use; tumor markers, like PSA or CA-15.

The different treatments that can be used to treat CUP are hormone therapy, chemotherapy, radiation and surgery.

For more information, contact Courtney Britton, librarian at Cancer Services of Greater Baton Rouge, at (225) 927-2273,, or visit the Education Center at 550 Lobdell Ave., Baton Rouge.


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