CUP FAQs
Q. How is CUP actually defined?
A. Histologically confirmed metastases with no identifiable primary site. That is to say, tissue taken from the site of a suspected secondary confirms that it is cancer, but when studied under the microscope and chemically tested the sample cannot be matched with that of a primary cancer.
Q. How many people are diagnosed with CUP?
A. Some 10,000 - 14,000 people are diagnosed with CUP in the UK each year – a higher incidence than fairly well known cancers such as pancreatic, leukaemia, ovary, uterus, kidney, brain or cervical cancers. In about a quarter the primary will never be identified.
Q. Does CUP affect children?
A. It is most often found in people who are in their 60s and over but it can affect people of all ages; incidence for children is 1% or less. Jo was 45 when diagnosed.
Q. Distinctions are often made between Carcinoma, Sarcoma, Melanoma or Lymphoma as the main Cancer Classifications - where does CUP fit in?
A. Most cancers of unknown primary are Carcinomas - carcinomas of unknown primary. Unlike Carcinoma, Sarcoma, Melanoma & Lymphoma have a characteristic histology allowing treatment without the need to locate a primary. Carcinomas are tricky and it is important to try and find the primary, which could be in several different places, to target treatment. There are clear management and treatment paths in place within the NHS to deal with sarcoma, melanoma, and lymphoma in all their manifestations (localised or metastatic). This is not yet the case with carcinoma of unknown primary.
Q. What proportion of all cancers is CUP?
A. In the UK and USA most sources seem to come out at around 5% although some suggest as much as 10%. Taking a world-wide view, it is widely accepted to be one of the 10 most common cancer types. It does depend on how CUP is defined and recorded.
Q. Diagnostic techniques presently lead to the primary being found in how many of those who are initially categorized as having CUP?
A. . It depends on the sub-set of CUP that is diagnosed e.g. Adenocarcinoma, Poorly Differentiated Cancer (explained in CUP classifications). The most pessimistic view is that the primary tumour is found in only 20% of cases. But figures vary significantly and this reflects the problem of how the statistics are gathered and the definition of CUP. Of course, once a primary is found it is no longer CUP.
Q. If you present with secondary cancers (metastases) does that mean you have CUP?
A. No. According to Cancer Research UK 10-15% of cancer patients present as Metastatic. The Institute of Cancer Research believe it to be nearer 70%.
Q. What are the commonest sites for metastases?
A. Lymph nodes, liver, bones, lungs.
Q. You refer to "true" CUP. How does this fit with other CUP definitions?
A. CUP is a complex and very varied phenomenon and it is therefore difficult to make simple distinctions that are also accurate. We use True CUP as a way of showing the point where all the tests that can be done, or it is desirable to do, have been completed and the doctors still do not know with any confidence where the cancer has come from. You could equally well view this as confirmed CUP. Up to that point, while tests are going on, or doctors have a good idea of where it might be, it is a state of undiagnosed, uncertain, undetermined, or unconfirmed CUP. These are not medically recognised terms in the CUP journey but they may help in understanding the problem.
Q. You have stressed the need to find the primary to target CUP but is there no way of treating CUP in general?
A. This is an area of research and "empiric" chemotherapy may well have an effect on the secondaries; but for the best results most oncologists believe it important to find the primary in treating carcinomas. There is a school of thought that CUP has a specific biological entity and if we could understand better the biology of cancer tumours the name of the cancer would be less important than its characteristics for determining treatment.
Q. Where does research show the most common primary sites when it is found?
A. Usually shown to be: lung, pancreas, biliary tract, gastrointestinal tract; but genetic profiling is beginning to question these findings.
Message board
Meeting Space
Join others affected by
CUP to share information
& gain support in a moderated forum
Events
Kate and Rebecca’s half marathon run raises £2000 through JustGiving
