Cancers of unknown primary (CUP) have always spread outside the organ they started in by the time they are diagnosed. If they had been found early, we would know where they started and they would not be classified as a cancer of unknown primary.
The American Cancer Society has specific recommendations about tests that may help detect breast, prostate, cervical, and colorectal cancers early, before they cause any symptoms.
But these cancers account for a fairly small portion of cancers of unknown primary. No screening tests have been proven to be effective in the early detection of many of the cancers that are likely to be diagnosed as cancer of unknown primary, such as pancreatic, stomach, and kidney cancers.
The American Cancer Society medical and editorial content team
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.
Last Revised: March 9, 2018
American Cancer Society medical information is copyrighted material. For reprint requests, please see our Content Usage Policy.