If you have symptoms, you usually start by seeing your GP. They will examine you and ask about your symptoms. If they think you might have cancer, they may refer you to a specialist for tests. Or if you have symptoms that are making you very unwell, you may be admitted to hospital straight away. In this situation, you will have tests while you are staying in hospital as an inpatient.
The first specialist doctor you see and the tests you have depend on your symptoms. For example,
- if you have bowel or stomach symptoms, your GP will refer you to a gastroenterologist. They treat problems of the digestive system.
- if you have kidney or bladder symptoms, you will see a urologist. They treat problems of the urinary system.
Doctors may look for the most common types of primary cancers first. The tests might show you have cancer, but the doctors still may not know where the cancer started. In this situation, the GP may refer you directly to a particular hospital team. This could be:
- the malignancy of unknown origin (MUO) team
- the cancer of unknown primary (CUP) team
- a rapid diagnostic centre.
The specialist team will arrange any tests you need. The tests you have depend on your symptoms. Your doctor will use national guidelines to decide which tests are right for you. The results of one test may suggest that another one would be useful.
You might have some of the following tests and scans:
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Blood tests can help doctors find out how organs such as the liver and kidneys are working. They are also used to find out the number of different blood cells you are producing (your full blood count).This information can help your doctors decide which area of the body to scan. For example, if the liver or kidneys are not working properly, your doctor may decide to scan them.
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You may have x-rays or scans to help find a primary cancer, or understand more about the type of cancer you have. We have more information about x-rays, mammograms, CT scans, PET-CT scans, MRI scans, and ultrasound scans in our A-Z of tests.
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Cameras that look inside the body (endoscopy)
An endoscopy is a test that looks inside the body using a thin, flexible tube with a camera on the end. This test may have different names depending on the area of the body. If you know the name of the test you are having, you can find it in our A-Z of tests. The most common types of include upper gastro-intestinal endoscopy, bronchoscopy, nasendoscopy, laryngoscopy, colonoscopy, cystoscopy and hysteroscopy.
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A laparoscopy is a small operation to look at organs inside your tummy (abdomen).
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If tests show that you might have cancer, you may have a biopsy. A biopsy means taking a sample of tissue or cells from an abnormal area. The sample is checked under a microscope for cancer cells. Some tests on a biopsy sample may give doctors more information about the type of cancer you have.
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Removing fluid for testing
You may have a build-up of fluid in your body. If the fluid collects around the lung, it is called a pleural effusion. A collection of fluid around the tummy (abdomen) is called ascites. Doctors can take a sample of this fluid and check it for cancer cells.
You have a local anaesthetic injection to numb the area. The doctor uses a needle to remove some fluid. Sometimes the doctor uses an ultrasound scan to help find the best area to get a sample from.
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You might have a bone marrow biopsyto check whether the cancer is affecting the bone marrow. Bone marrow is a spongy material in the middle of our bones. It is where blood cells are made.
Other tests on the biopsy
Some other tests can be done on a biopsy sample. They may give doctors more information about the type of cancer you have.
You might have some of the following tests and scans:
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Immunohistochemistry test
This test uses antibodies to find out whether there are particular proteins on the surface of the cell. These may be linked to some cancer types.
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This test looks at the changes in the chromosomes in a cell. Changes in the structure of some chromosomes can be linked to some cancer types.
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Hormone and protein receptor test
This test looks at cancer cells with receptors. Some cancer cells have receptors which certain types of hormones or proteins to attach to. Identifying these may help doctors find out where the cancer cells came from.
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Gene expression-based profiling (GEBP)
GEBP looks for patterns of genes in the secondary cancer tissue. These patterns can help doctors find out what the primary cancer might be. This can help them decide which other tests you should have and which treatments are most suitable for you.
At the moment, gene profiling tests for people with CUP are not usually available on the NHS. But you may be able to have them as part of a clinical trial. You can find further information about gene expression-based profiling on the Cancer of Unknown Primary Foundation website.
Waiting for test results
Waiting for test results can be a difficult time. It may take from a few days to a couple of weeks for the results to be ready. You may find it helpful to talk with a partner, family member or close friend. Your specialist nurse or a support organisation can also provide support. Or you can talk to one of our cancer support specialists for free on 0808 808 00 00 (7 days a week, 8am to 8pm).
FAQs
Carcinoma of unknown primary (CUP) is a rare disease in which malignant (cancer) cells are found in the body but the place the cancer began is not known. Cancer can form in any tissue of the body. The primary cancer (the cancer that first formed) can spread to other parts of the body. This process is called metastasis.
How long can you live with cancer of unknown primary? ›
Median survival in patients with cancer of unknown primary origin ranges from 11 weeks to 11 months. The 5-year overall survival rate is about 11%.
Is cancer of unknown primary always stage 4? ›
There is no staging system for cancer of unknown primary (CUP). This is because the cancer has already spread and doctors don't know where the original cancer started.
What is the hardest cancer to cure? ›
The 10 deadliest cancers, and why there's no cure
- Pancreatic cancer.
- Liver cancer and intrahepatic bile duct cancer.
- Esophageal cancer.
- Lung cancer and bronchus cancer.
- Acute myeloid leukemia.
- Brain cancer and other nervous system cancer.
- Stomach cancer.
- Ovarian cancer.
If it can't be found, the treatment path can be less clear but treatment can still be given. To help plan the treatment, your doctor will try to learn as much as possible about the spread of the cancer, the cells involved, your symptoms and your medical history.
Can cancer of unknown primary be treated? ›
Doctors can't cure most cases of CUP. This is because the cancer has already spread from one part of the body to another. But treatment can control it, relieve symptoms, and give you a good quality of life. Your doctor may also suggest holding off treatment for a while if you don't have many symptoms.
What is the mortality rate for cancer of unknown primary? ›
In 2022, it is estimated that a person has a 1 in 139 (or 0.72%) risk of dying from cancer of unknown primary site by the age of 85 (1 in 120 or 0.83% for males and 1 in 165 or 0.61% for females). In 2020, the age-standardised mortality rate was 7.9 deaths per 100,000 persons (9.5 for males and 6.5 for females).
What is the cause of unknown primary cancer? ›
Key Points. Carcinoma of unknown primary (CUP) is a rare disease in which malignant (cancer) cells are found in the body but the place the cancer began is not known. Sometimes the primary cancer is never found. The signs and symptoms of CUP are different, depending on where the cancer has spread in the body.
What is the most common type of cancer of unknown primary? ›
Adenocarcinomas: About six of every 10 cancer of unknown primary cases are adenocarcinomas, meaning they began in gland cells. Most frequently, the primary sites are the lung, pancreas, breast, prostate, stomach, liver or colon.
Does all stage 4 cancer mean death? ›
Stage 4 cancer is not always terminal. It is usually advanced and requires more aggressive treatment. Terminal cancer refers to cancer that is not curable and eventually results in death. Some may refer to it as end stage cancer.
If defining "fastest-killing" cancer is based on which cancer has the worst 5-year relative survival rate, then it would be a tie between pancreatic cancer and malignant mesothelioma (a relatively rare cancer in the U.S. with about 3,000 cases a year).15 However, there are some differences in survival rates for these ...
What are the top 3 deadliest cancers? ›
Lung and bronchus, colorectal, pancreatic, and breast cancers are responsible for nearly 50% of all deaths.
What cancer has the poorest prognosis? ›
Which cancer has the lowest survival rate? There are 6 cancers with low survival rates: lung cancer, liver cancer, brain cancer, esophageal cancer, stomach cancer, colon and rectal cancer. According to experts, the above 6 cancers have low survival rates mainly because these diseases are difficult to recognize.
How long can you live with unknown cancer? ›
around 16 out of 100 people (around 16%) survive for 1 year or more. around 10 out of 100 people (around 10%) survive for 3 years or more.
What doctors don't tell you about cancer? ›
5 things they don't tell you about life after cancer
- 1) Fatigue can last years after treatment. ...
- 2) Your sleep habits may change. ...
- 3) Anxiety and depression are common. ...
- 4) You may struggle with body changes. ...
- 5) Treatment may cause late and long-term effects. ...
- Survivorship programs offer support even after treatment ends.
Approach to diagnosing a cancer of unknown primary
Endoscopy exams to look at organs through a lighted tube placed into a body opening such as the mouth, nose, or anus. Blood tests. Biopsies to remove samples of tissues or cells and look at them with a microscope or test them in the lab.
How long can you live with undetected cancer? ›
If you're wondering how long you can have cancer without knowing it, there's no straight answer. Some cancers can be present for months or years before they're detected. Some commonly undetected cancers are slow-growing conditions, which gives doctors a better chance at successful treatment.
What is cancer of unknown primary stage? ›
Key Points. Carcinoma of unknown primary (CUP) is a rare disease in which malignant (cancer) cells are found in the body but the place the cancer began is not known. Sometimes the primary cancer is never found. The signs and symptoms of CUP are different, depending on where the cancer has spread in the body.
What is a cancer with no primary source? ›
Cancer of unknown primary (CUP) means that cancer spread has been found in your body (secondary cancer), but your doctors can't find where the cancer started (the primary cancer).
