Treating cancer in someone with dementia

The cancer treatment offered to a person with dementia will depend on their individual situation, but also on the stage of the dementia.

Dementia and cancer treatment

The cancer treatment offered to a person with dementia will depend on their individual situation. But it will also depend on the stage of the dementia. Doctors and nurses who specialise in cancer can talk to you about which cancer treatments might help.

The main treatments for cancer are:

Benefits and advantages of cancer treatment

Some people with cancer and dementia will be offered the standard treatment for the cancer. They may sometimes have to spend time in hospital.

The person you care for is likely to have side effects from cancer treatment. These are usually temporary and can be controlled with medicines. But some people have longer-lasting side effects known as late effects. We have more information on the late effects of cancer treatment.

For some people, treatment will cure the cancer. Other people may not respond to the treatment. This means that they may have the side effects of treatment without any of the benefits.

Some people may not have standard treatment. This might be because they are not well enough or have other health problems. Other people may choose not to have the standard treatment. Instead, they might have other treatments with:

  • lower doses of medicine
  • fewer treatment sessions.

They will usually spend less time in hospital and have fewer side effects. These types of treatment are given to control the cancer, but they will not get rid of it completely.

Supportive or palliative treatment

Sometimes the treatment stops working. If this happens, the person receiving it can still be given supportive or palliative treatment to help control symptoms. The person may also choose to stop treatment at any time. If they do, they will still be offered supportive treatments.

Some people may choose not to have treatment for the cancer but go straight to palliative care. If someone is having problems with symptoms or side effects, they can have supportive treatments for any stage of cancer.

Making treatment decisions

Talk to the person you care for about whether they would like to have treatment and what they might prefer. You may find it helpful to read our booklet, A guide for people with cancer and dementia, together.

It might be helpful for you to go with them to talk to their doctor about treatment options. You may also be able to talk about the possible benefits and side effects of treatment with a nurse.

We have more information about making treatment decisions.

Giving consent

Before someone has any treatment, their doctor will explain the aims of the treatment. They will usually ask them to sign a form saying that they give permission (consent) for the hospital staff to give treatment. No medical treatment can be given without the person’s consent.

Before they are asked to sign a consent form, the person you care for should be given full information about:

  • the type and extent of the treatment
  • its advantages and disadvantages
  • any significant risks or side effects
  • any other treatments that may be available.

 If the person you care for is not able to give consent, they may still be able to have treatment if their doctor thinks it is in their best interest.


For consent to be valid, the person giving consent must have capacity. This means that they must be able to:

  • understand all the information given to them
  • remember the information for a specific time
  • consider the benefits and risks of treatment
  • make an informed decision.

Some people with dementia do have the capacity to make informed decisions. For others, the ability to make specific decisions can be affected. The specialist doctor looking after them may need to check if they can make an informed decision about treatment. They may use a hospital assessment to do this.

If someone is not able to make a decision

Health professionals can still give treatment if they believe it is in the person’s best interests. But they must try to get advice about the person’s wishes from a partner, family member or friend.

If the person with dementia does not have family or friends who can help, they may be referred to an independent advocate. This is someone who can support and act for the person through making any decision, such as whether to have serious medical treatment. The Social Care Institute for Excellence (SCIE) has more information on independent advocates.

The person you care for may have given someone legal power to make decisions for them. This is called lasting power of attorney. We have more information on advance care planning.

It can help the person you care for to think ahead, before their ability to make decisions is affected. They can write down how they would like to be cared for. It is helpful to give clear instructions about any treatments they would or would not want to have. This is known as making advance decisions.

If you are the carer

If you care for someone with cancer and dementia, you may have to help them decide about treatment or make decisions for them. It can be difficult to know what to do. Talk to the dementia specialist doctor or nurse. They can give you advice.

Alzheimer’s Society has a fact sheet called Making decisions and managing difficult situations that you may find useful.

Appointments and hospital visits

If you are the main carer of someone with cancer and dementia, you will probably go with them to their GP and hospital appointments. You may also visit the hospital during their treatment.

During appointments

During appointments, you can help by remembering and writing down information. You can also help the person you care for describe any symptoms or problems they are having. If they had any questions before the appointment, you can prompt them and help them to remember what they wanted to ask.

The cancer doctor, nurses and any other health professionals should know that the person you care for has dementia. It is usually recorded on their medical notes and referral letter. But it can be useful to explain what this means – for example, how well the person you care for can remember things and take in information.

Communication tips

You can ask the doctor or nurse to communicate in ways that are helpful. It might help if the health professional:

  • faces the person you care for, at the same level
  • gives information in a quiet place without distractions
  • makes eye contact when talking
  • keeps information simple by avoiding medical words
  • repeats things if necessary
  • breaks information down into small chunks that are easy to understand.

Recording the appointment

You can also ask the doctor or nurse if you can record the appointment. This means you can go back over what was said later. This can help with making decisions about treatment. It may also be reassuring, and you can pass it on to other family members if they want to know more.

Most mobile phones can be used to make an audio recording or voice note. You do not have to record the whole conversation. You can ask the doctor or nurse to make a short summary of what was said at the end.

Hospital admissions

The person you care for may have to stay in hospital or go to the hospital for treatment. It is important that the team looking after them knows about their everyday needs. This might include information such as:

  • how they normally communicate
  • how they get around
  • whether they need any special equipment, such as a hearing aid, walking stick or raised toilet seat
  • whether they need help with daily activities such as washing, dressing or eating
  • whether they have any special dietary needs
  • how they behave when they are in pain.

Giving support

If the person you care for is going to hospital for a test or treatment, you can ask to be there. For example, you may be able to help keep them calm or still during a scan or while they are having treatment through a drip. This may not be suitable for all types of test or treatment. Ask the doctor or nurse if it is possible. Or you could check with the department that the appointment is at. Some hospitals may allow you to visit outside usual visiting hours if it helps to keep the person you care for calm.

Alzheimer’s Society has an information form called This is me. It can be filled out by people with dementia and their carers. The form is helpful for the person with dementia if they are in an unfamiliar place, such as a hospital or respite care. It can help if they are having problems communicating.

We have more information on talking to healthcare staff.

Getting to appointments

Sometimes getting to and from hospital can be difficult and expensive – especially if the person you care for needs help to move around. Here are some things you could do to try and make this easier:

  • Ask for a telephone consultation

    A telephone consultation will not always be possible, but it may reduce the number of times you have to get to and from hospital.

  • Use hospital transport

    Hospital transport may vary. It will usually take longer, as more than one patient will be transported at a time. Ask the nurse what is available. Or phone the department where the appointment will be.

  • Specialised driving services

    Specialised driving services for elderly or disabled people are available in some areas. They will charge a fee for this service.

Waiting at hospital for appointments may be more difficult for someone with dementia. It can help to take something they enjoy to pass the time, such as:

  • books
  • magazines
  • puzzles
  • a twiddle muff – a knitted hand muff with objects of different textures such as beads, buttons or ribbons to keep the person’s hands occupied.

About our information

  • References

    Below is a sample of the sources used in our bowel cancer information. If you would like more information about the sources we use, please contact us at

    Alzheimer’s Society. Dementia 2015: Aiming higher to transform lives. 2015.

    Gosney et al. Dementia and Cancer: A review of current literature and practices. 2013.

    The Dementia Engagement and Empowerment Project (DEEP) Guide: Writing dementia-friendly information. 2013.

  • Reviewers

    This information has been written, revised and edited by Macmillan Cancer Support’s Cancer Information Development team. It has been reviewed by expert medical and health professionals and people living with cancer. It has been approved by Chief Medical Editor, Professor Tim Iveson, Consultant Medical Oncologist.

    Our cancer information has been awarded the PIF TICK. Created by the Patient Information Forum, this quality mark shows we meet PIF’s 10 criteria for trustworthy health information.

Date reviewed

Reviewed: 01 November 2020
Next review: 01 November 2023

This content is currently being reviewed. New information will be coming soon.

Trusted Information Creator - Patient Information Forum
Trusted Information Creator - Patient Information Forum

Our cancer information meets the PIF TICK quality mark.

This means it is easy to use, up-to-date and based on the latest evidence. Learn more about how we produce our information.