Rare cancers

What is a rare cancer?

Experts in the UK and European Union say a cancer type is rare if fewer than 6 in 100,000 people are diagnosed with it each year. For some clinical trials, a cancer is rare if doctors diagnose fewer than 2 in 100,000 people each year.

Examples of rare cancers include:

• anal cancer

• gallbladder cancer 

• Hodgkin lymphoma

• eye cancer

Rare cancers make up about 24 out of every 100 (about 24%) cancer cases diagnosed in the UK and European Union per year. This also includes children and young people’s cancers.

Rare types of common and less common cancers

The most common cancers in the UK are:

• breast cancer

• prostate cancer

• lung cancer

• bowel cancer

Examples of less common cancers include: 

• melanoma skin cancer

• oesophageal cancer 

• bladder cancer

• non-Hodgkin lymphoma

• pancreatic cancer 

Some people may have a rare type of one of these common or less common cancers.

Different cell types

Cancers can start in different types of cell. For example, bowel cancer can start in glandular cells that produce ​mucus​ . Doctors call this type of cancer adenocarcinoma. Adenocarcinoma is the most common type of bowel cancer. But bowel cancer can also start in ​squamous cells​ . Bowel cancer that starts in squamous cells is a rare type of cancer. 

Find out more about the types of cell cancer can start in

Unusual places

Some common types of cancer can also start in unusual places in the body. For example, cutaneous T cell lymphoma is a rare type of non-Hodgkin lymphoma that starts in the skin.

Treatment

Doctors treat some rare cancers in the same way as the more common cancers of that type. But other rare types get treated differently. Rectal cancer is a type of bowel cancer. Doctors treat squamous cell cancer of the rectum differently to rectal adenocarcinoma.

Why can it take longer to diagnose rare cancers?

It can take longer to diagnose a rare cancer. This can be because:

• the symptoms might be unusual and less recognisable than for more common cancers

• you might need more tests to find out what type of cancer it is

• some tests may need to be done at other hospitals

• your doctor may need to get advice from doctors in other hospitals

Your specialist doctor asks you to have tests to first work out whether you have cancer or not. If you do, they can then find out exactly what type it is. This may mean you need more tests.

Doctors diagnose most types of cancer by taking a sample of tissue (biopsy) from where they think the cancer is. For example, if they think the cancer is in your breast they take a biopsy from your breast. If they think the cancer is in your blood, they normally ask for a sample of your blood to be taken. Your doctor sends the sample to a specialist doctor called a pathologist. They test the sample in the laboratory to see if it contains cancer cells.

The pathologist might need to do a number of different tests on your biopsy or blood sample. Or they might need to send the sample to a specialist laboratory to be tested. Depending on the test, it could take a few days and sometimes weeks to do the test and get the results. This means it can take longer to get a diagnosis.

For very rare types of cancer your specialist doctor may need to get advice from experts about your symptoms and test results. These might be doctors in other parts of the UK or in other countries.  Your doctor might not be able to tell you much until they have spoken to these experts. You might find this worrying and frustrating as you don’t know what you are dealing with. Sometimes you might feel like your doctor is hiding something. But it is all part of trying to work out what they can do to help you.

Once your doctor knows what type of cancer you have, they talk with you about what happens next. They may refer you to a specialist cancer centre for treatment. Or they may need time to research and speak with other doctors who have treated people with this type of rare cancer.

Getting a second opinion

Some people may want to ask about a second opinion before deciding on treatment. Speak to your doctor about this. It is likely they will have already discussed your case with other health professionals to work out the best treatment plan for you. This may mean you have had a second and third opinion without even knowing.

If you would still like another opinion, ask your specialist to refer you to another doctor who looks after people with this type of cancer. It’s better to arrange this through your specialist as they can send the second doctor all your notes and test results.

Do remember that a second opinion does not necessarily mean that the second doctor will take over your care. Your treatment will usually still be managed by your original specialist.

Find out more about getting a second opinion

Treatment for rare cancer

A team of doctors and other health professionals discuss the best treatment and care for you. They are called a multidisciplinary team (MDT). Your doctor will then talk with you about the treatment they recommend. The treatment you have depends on several factors including:

• where the cancer is

• how big it is and whether it has spread (the stage)

• how abnormal the cells look under a microscope (the grade)

• your general health and level of fitness

Your doctor will discuss the treatment options, their benefits and possible side effects with you.

Some of the treatments for rare cancers include:

• ​surgery​

• ​chemotherapy​

• ​radiotherapy​

• ​hormone therapy​

• ​targeted cancer drugs​

• ​immunotherapy​

• ​stem cell​ or ​bone marrow transplant​

• having treatment as part of a ​clinical trial​

You may have more than one of these treatments. Your doctor and specialist nurse are the best people to speak to about your particular cancer.

Find out more about the different treatment types

Preparing for treatment

There are things you can do to help you feel more in control of your physical and mental health during this time.

Research shows that focusing on certain lifestyle changes in the time you have before starting treatment can:

• help you cope better with side effects

• improve your long term health

In the hospital, preparing for treatment is also called prehabilitation or prehab.

Find out more about prehabilitation

Research into rare cancers

Researchers in the UK and around the world are looking for better ways to diagnose and treat rare cancers. They do this by asking people to take part in clinical trials. But it can be more difficult to find a clinical trial for a rare cancer than it is for more common cancers.  

Challenges in research for rare cancer

There might be fewer clinical trials for rare types of cancer than for more common cancers. There can be a number of reasons for this including:

• there are fewer people with a specific rare cancer to take part

• the people who can take part  may not live in the same country – this can make the trial difficult to organise and run

• only a small number of hospitals may take part in the trial

• if someone is diagnosed later with a rare cancer, they may not be able to take part in a clinical trial

• less money is made available for researching rare cancers

Getting enough people to take part is very important to the success of a trial. The results wouldn't be powerful enough if the trial involves too few people. For example, results wouldn’t be able to prove whether one type of treatment is better than another.

Our research into rare cancer

Cancer Research UK has contributed to several advances for people with rare cancers. We ran some of the first trials for people with:

• a type of eye cancer called uveal melanoma

• ​neuroendocrine tumours​  

We continue to fund and research clinical trials into rare cancers.

Find out more about our research into rare cancers

Research into genomics

Genomics means to study the ​DNA​  in a complete set of ​genes​ . A complete set of genes is also called a genome.

The genome is made of DNA. A small amount of the DNA is inside the genes. These tell the body how to make, run and repair itself. The rest of the DNA is around the genes. This controls the genes and the genome. Scientists link cancer to changes in the genome.

Researchers are looking at the DNA in a person’s cancer cells, as well as their healthy cells to see if there is anything different. They hope these differences will tell them which treatments are best for that cancer type.

The Department of Health and Social Care is running the 100,000 Genomes project. It aims to understand what role genes play in health and disease. An area of focus within this project is cancer, including rare cancer. 

Read more about the 100,000 Genomes project

There are other research studies looking at rare cancers and those that affect people at a young age to find out more about cancer genetics and if they can develop further tests.

Rare Cancers Working Group

The Rare Cancers Working Group (RCWG) is a partnership between:

• a variety of different research organisations

• professional societies

• charities

• rare cancer networks

• patient groups

• healthcare and education providers

This working group was set up to raise the awareness of rare cancers. Their work includes improving:

• the quality of clinical trials into rare cancers

• access to treatments for rare cancers

• how healthcare is organised for people with rare cancers

• information on rare cancers

• the education of healthcare professions about rare cancers

Find out more about the Rare Cancers Working Group

If you would like to take part in a clinical trial

Speak to your doctor or specialist nurse if you are interested in taking part in a clinical trial. If they have particular expertise in your type of cancer, they may be part of a research group. Even if they are not, they might be able to find out if there are any trials you can take part in.

You can also look at our searchable database for rare cancer trials in the UK. You can choose from the list of cancer types or type the name of the cancer into the search box.

Talk to your specialist if you see a trial you think you might be able to take part in.

Find a clinical trial

Coping with a rare cancer diagnosis

Many people can feel isolated if they have a rare type of cancer. It might take longer to get a diagnosis and to start treatment which can make you anxious. And you may not know anyone else with this type of cancer.

You might need to go to a specialist hospital for treatment. This could involve travelling further than your local hospital. But it can be reassuring to know that a specialist team is caring for you. You are also more likely to meet someone else with your cancer type.

There are things you can do, people who can help and ways to cope with a diagnosis of cancer. But you may need to give yourself time before you find out more. When you are ready, you can ask your doctor or specialist nurse what help and support are available to you. They can also tell you about support available for your family and friends.

Read about coping with cancer