Getting diagnosed with cancer of unknown primary

Most people are diagnosed with cancer of unknown primary (CUP) after they become unwell and go to accident and emergency (A&E). Others start by seeing their GP if they have symptoms that could be due to cancer. The GP examines you and might refer you for tests or to a specialist. Some people may be diagnosed during tests for another health condition.

If your tests show that you have cancer that has spread (a secondary cancer), you may have further tests to look for where the cancer started (the primary tumour) and to see if it has spread anywhere else in the body. If doctors can't find the primary cancer, it is CUP.

Sometimes doctors find the primary cancer at a later date. When this happens, the cancer is no longer a CUP and your treatment will follow the guidelines for the specific cancer type.

Seeing your GP

You should see your GP if you notice a change that isn't normal for you. Read about what happens when you see your GP and how to get the most out of your appointment.

Referral to a specialist

Your GP can arrange for you to see a specialist doctor. Find out which specialist you might see and what to expect. 

Tests for cancer of unknown primary

The tests you have depends on your symptoms. Find out which tests you might have to diagnose CUP and what to expect during the tests. 

Last reviewed: 
10 May 2021
Next review due: 
10 May 2024
Coronavirus and cancer

We know it’s a worrying time for people with cancer, we have information to help.

Read our information about coronavirus and cancer