Immunotherapy for Cancer

What is Immunotherapy?

Immunotherapy is a common biological therapy against cancer which helps support the body’s own immune system to target and fight cancer.

This type of therapy helps the immune system recognise cancerous cells and boost immune cells to help them fight against the cancer.

The job of the immune system is to identify and destroy abnormal cells and other threats to health. Cancerous cells are abnormal, and immune cells are often found located around the site of a tumour, showing that the body recognises the abnormal cells and is responding to them as best it can.

While the immune system can help to prevent or slow cancer growth, cancerous cells have complex and intuitive means to avoid detection and destruction, allowing them to keep growing. These defences include:

• Genetic modifications to make them less visible to the immune system
• Molecules which act to deactivate immune cells
• Making the surrounding environment hostile to immune cells
• Affecting non-cancerous cells in the vicinity to change how immune cells respond

What is the History of Immunotherapy?

The roots of immunotherapy therapy for cancer goes back to the mid 1800s, when work carried out by Busch and Fehleisen showed that injecting Streptococcus bacteria reduced tumours in melanoma patients. Later in the 1800s, an American surgeon named Coley, now commonly known as the ‘father of immunology’ attempted to use the immune system to help treat bone cancer with apparently positive results, and subsequently treated hundreds of patients and inoperable tumours over a 40 year span in a similar fashion. ‘Coley’s Toxins’, as they were known, gradually disappeared from use as chemotherapy and radiotherapy became common practice.

During the same period a Berliner named Ehrlich theorised that the cells contained proteins which could recognise certain molecules and bind to them. This is known as the ‘receptor theory’ and paved the way for drug-specific receptors, a fundamental concept in immunotherapy.

Various other discoveries were made during the 1900s including Morton’s study of over 150 melanoma patients treated by directly injecting tumours with BCG, resulting in tumour regression in 91% of patients.

Skipping forward to the latest developments in immunotherapy, the 2018 Nobel Prize was awarded to Allison and Honjo for their ‘discovery of cancer therapy by inhibition of negative immune regulation’. As we can see here, immunology is a growing and ever-expanding form of cancer treatment with showing benefits for a wide range of cancers.

How Does Immunotherapy Work?

Immunotherapy is a form of cancer treatment which boosts a person’s immune system and equips it to better fight cancer. This may mean helping the body recognise cancerous cells, boost its ability to fight cancer, or increase the strength of your immune system. It uses organic substances found in the body and created in laboratories to boost your natural defences. It can help slow or even stop the growth of cancer cells and prevent it spreading in some cases.

There are a number of ways this can be done, and the best form of immunotherapy for your cancer type will depend on a number of factors including the stage and type of cancer you have. It is often used in conjunction with other forms of cancer treatment as a combination therapy.

Immunotherapy Treatment Types

There are a number of types of immunotherapy used in cancer therapy. These include:

Immune checkpoint inhibitors

 Immune checkpoints are part of the human immune system, designed to limit immune responses so as not to destroy health cells while carrying out their job.

Cancer cells have developed ways to use these checkpoints to avoid detection. Checkpoint inhibitors do not attack the cancer directly, instead they ‘switch off’ the off signal to stop the attack. This allows the immune system to attack the cancerous cells where it otherwise would not.

Treatment vaccines

Cancer treatment vaccines help train the immune system to recognise and destroy harmful bodies in the same way other vaccines do. Some vaccines are used as a preventative measure, such as the HPV vaccine which can be used to help prevent cervical, vaginal, vulvar an anal cancer, and the Hepatitis B vaccine which may be used to help to prevent liver cancer.

Other cancer vaccines are used to treat existing cancers by boosting the ability of the immune system to seek and destroy cancerous cells. Some cancer vaccines use a sample of a person’s tumour to help the body recognise and attack those cells. This personal vaccine process will only work on that individual. Other cancer vaccines are not specific to individuals.

T-cell transfer therapy

This treatment helps your T cells fight cancer. T cells are white blood cells which seek out foreign and threatening bodies. There are three types of T cell, cytotoxic, helper and regulatory. All three must react to foreign antigens to initiate an immune response. During T cell immunotherapy, immune cells are taken from the tumour area and the most active against the tumour are selected and/or edited to develop a stronger attack on your cancerous cells. These cells are then reproduced at scale, and injected back into the body to return to the tumour and continue to fight.

Immune system modulators

There are a number of immune system modulator agents for treating cancers, which are often used in advanced cases. These include:

• Biological response modifiers – Used to stimulate the immune response. These drugs can help stop tumours creating new blood vessels, thereby preventing them from growing
• Cytokines – Cytokines are proteins created by white blood cells which contribute to the body’s immune response.
• BCG – BCG (bacille Calmette-Guerin) is a vaccine primarily used to prevent tuberculosis; however it has been found to initiate an immune response to cancer when injected into the bladder, and as such can be used to treat this form of cancer.

Monoclonal antibodies

Recently monoclonal antibodies have been approved for emergency use in COVID-19 cases, but mainly they are used to treat cancer. These proteins are grown in a laboratory and are designed to mimic an immune response. They can take one of a number of roles including:

• Detecting and flagging cancer cells
• Triggering an immune response which can lead to cell membrane destruction of cancerous cells
• Blocking immune system inhibitors to give cancer-fighting cells more strength
• Preventing blood vessel growth in tumours
• Blocking tumour growth by blocking cell growth
• Delivering radiotherapy
• Delivering chemotherapy
• Binding cancer and immune cells to help promote immune system attack
• Directly attacking cancer cells and causing self-destruction within them

When is Immunotherapy Commonly Used?

Immunotherapy is not effective on all types of cancer, may be able to treat all cancers to some degree in the future. It is sometimes used to prolong life in advanced stage cancer patients.

Whether immunotherapy is suitable for you depends on a number of factors including:

• Other cancer treatments you have already had
• The stage of your cancer
• The type of cancer you have

At present it is mainly used to treat:

• Lymphoma
• Liver cancer
• Bladder cancer
• Colorectal cancer
• Lung cancer
• Kidney cancer
• Head and neck cancer
• Thyroid cancer
• Leukaemia
• Skin cancer
• Breast cancer
• Cervical and ovarian cancers
• Prostate cancer

It may also be occasionally used in the treatment of pancreatic , uveal melanoma and other cancers, with a number of clinical trials still on-going to help improve effectiveness.

What Are The Benefits of Immunotherapy Treatment?

The benefits of immunotherapy include:

Ability to boost other forms of treatment – Other therapies can return more positive results when used in combination with immunotherapy.

Cancer is less likely to reoccur – Once your body’s natural defences have recognised and attacked your cancer, your immune system stores that information and will attack again should it return.

High Accuracy – Immunotherapy is a highly targeted therapy which poses no threat to healthy cells.

Fewer side effects – Because immunotherapy uses the body’s natural defences and only targets the immune system not the cancer itself, patients undergoing immunotherapy may experience less side effects than those undergoing other forms of treatment.

Efficacy where other treatments produce poorer results – Some types of cancer respond to immunotherapy more often that chemotherapy, radiotherapy and other forms of treatment. Skin cancer is a good example of this.

What to Expect When Receiving Immunotherapy? 

If you and your care team decide immunotherapy is a good choice of treatment for you, the process and schedule of your treatment will vary according to the type of immunotherapy chosen and type of cancer you have.

How is Immunotherapy Given?

You may be given immunotherapy treatment in one of a number of ways:

Intravesical – If you have bladder cancer, immunotherapy is applied directly to the bladder via a syringe.

Oral – Immunotherapy drugs are often administered in pills or tablets to be taken orally.

Topical – Some immunotherapy treatments come in a cream which applied to the skin. This form of therapy is common when treating skin cancer.

Intravenous (IV) – In this form of treatment drugs are administered directly into the vein. 

If you decide to have immunotherapy treatment, your physician will discuss with you how it will be given to you prior to having it.

How Often is Immunotherapy Administered?

How often you receive immunotherapy depends on the type of treatment you receive. This will depend on a number of factors including:

• What type of cancer you have
• The stage of your cancer
• The type of immunotherapy chosen
• How your body reacts to the therapy

You are likely to receive your treatment in cycles where treatment is administered, followed by a period of rest. You may have treatment every day, once a week, or once a month depending on the type of therapy chosen and the aforementioned factors. Depending on how often you receive the treatment may have an impact on your life and therefore, it’s important to think of all the implications of this treatment and any treatment in fact before undergoing it.

Preparing for Immunotherapy

Before starting a course of immunotherapy it is important to ensure your doctor knows if:

• You have an autoimmune disease
• You have liver disease
• You have had an organ or stem cell transplant
• You are pregnant, or plan to be
• Are breastfeeding or plan to start
• You experience breathing difficulties

Make sure they know your complete medical history and tell them about any medications you are currently taking.

The schedule of your immunotherapy sessions are very important too. Be sure you can attend all sessions and leave plenty of free time around the appointment to prepare and recover, as well as counter any delays.

Coping After the Therapy

How you feel after immunotherapy depends on what type of treatment you receive. You may experience a number of side effects.

Potential Side Effects from Immunotherapies

As with all forms of cancer treatment, you may experience side effects. These will vary depending on the type of immunotherapy you receive, and the type of cancer you have. In many cases the immunotherapy patients experience less side effects that those receiving other forms of treatment as it is using the body’s own natural defences.

Common side effects include:

• Flu-like symptoms
• Fever
• Tiredness
• Headache
• Weight gain
• Itching
• Redness
• Swelling
• Diarrhoea
• Loss of appetite

Less common side effects include:

• Autoimmune disorders
• Shortness of breath
• Pneumonitis – inflammation of lung tissue
• Changes in blood pressure
• Yellowing of the skin and eyes

You should contact your treatment centre if you experience the following side effects:

• A high temperature
• Pain when you urinate
• Blood in urine or stool
• Chest pain
• Shortness of breath

Side effects of immunotherapy will vary from person to person. Your care team will help and advise you on the best ways to manage any side effects which you experience from your treatment.

Signs the Treatment is Working

A number of immunotherapy patients experience pseudo-progression during immunotherapy. This is a condition whereby solid-state tumours increase in size temporarily, before beginning to shrink.

During and after treatment your care team will arrange regular blood tests, check-ups, and scans where appropriate to gauge your progress. If immunotherapy works for you, you can expect to see the tumour stabilise, stop growing, or begin to shrink.

Some people experience a delayed response to immunotherapy, so initial results may seem a little slow. Success rates depends on a number of factors including the type and stage of the cancer you have. Immunotherapy can produce long lasting results in around 25% of patients. This treatment type does not work for everyone. In the event that immunotherapy does not work for you, your care team will advise alternative therapies.

Nutrition Advice When Receiving Immunotherapy  

While receiving immunotherapy therapy to help combat cancer, your body needs support from your diet and lifestyle choices to help it fight cancer and support your immune system and overall health. Make sure to eat a varied diet full of fruit and vegetables, and proteins to help keep your body strong.

Try to ensure you intake the recommended daily amount of vitamins and minerals each day through your diet. A number of these help build cells and keep them healthy, repairing damage and preventing further issues. 

Make sure you take the recommended daily amount of exercise as and when you can and try to maintain a daily regular exercise regime as much as you can.

Alternatives to Immunotherapies

There are a wide range of cancer therapies available, the most effective options for you will take into account a number of key factors in your specific situation. These should be discussed at length with your care team. Ensure you have all the information you need to make the right decision for you.

Immunotherapy in the News

Immunotherapy appears in the news frequently due to the large number of trials and new discoveries being made often.

Recent research shows new steps forward in immunotherapy treatment for melanoma, breakthroughs in patients accessing immunotherapy for cancer, and success stories in immunotherapy for breast cancer.

You can read more about immunotherapy in the news from a wide range of sources. Here are just a few:

MedicalXpress

Cancer Research

The Independent

Explore Your Treatment Options

Immunotherapy is a potentially effective option for a number of cancers, however the most effective treatment for you will take into consideration a range of factors based on your individual situation.

Oncolomed can help you explore your options and find the right treatment by facilitating second opinions and cancer treatment through our network of leading clinics and oncologists.

See how we can compassionately guide you in your cancer treatment journey by exploring our range of services.

Alternatively, read our patient stories to see how we have helped patients across the globe in their fight against cancer.