Immunotherapy

Immunotherapy is a way of treating cancer by helping your own immune system to recognise and attack tumour cells more effectively. Rather than directly affecting cancer cells (as chemotherapy does), immunotherapy works by ‘taking the brakes off’ immune cells, or by helping immune cells can get into the tumour and stay active.

In colon cancer, rectal cancer, pancreatic cancer, liver cancer and bile duct cancers, immunotherapy is now an established option for some people and an emerging option for others. For some people – such as those with mismatch repair deficient / MSI-high metastatic colorectal cancer, or advanced bile duct and liver cancers – it can be one of the main pillars of treatment.

We rarely think about immunotherapy in isolation. Instead, we design a combined plan that may also include chemotherapy, targeted therapy, stereotactic radiotherapy (SABR), and surgery for peritoneal metastases or liver secondaries. The aim is always the same: increase the chance of cure where possible, and otherwise extend life and maintain quality of life in a way that fits your priorities.

Sometimes we give immunotherapy as the very first treatment; sometimes we introduce it later if the timing is right. Treatment is always personalised to your goals and to what we can realistically achieve. This page sits alongside my conventional chemotherapy and targeted therapy information and is designed to help you understand when and how immunotherapy might feature in your care.

Most of the immunotherapy drugs I use are called ‘immune checkpoint inhibitors’. They are antibodies that block proteins such as PD-1, PD-L1 or CTLA-4 which normally act as brakes on immune cells. By lifting these brakes, T-cells (which are the front line of the body’s defence against cancer and infection) can recognise and attack cancer cells more effectively. Your body often generates its own immune response against the cancer– the immune checkpoint inhibitor unlocks these capabilities. New approaches, such as CAR T-cell immunotherapy, oncolytic virotherapy, cancer vaccine treatments, and drugs targeting the tumour microenvironment (which is the tissue that surrounds the cancer cells), are on the horizon and I regularly network globally to stay up-to-date and ensure my patients have access to a clinical trial where appropriate.

In some cancers, immunotherapy works best when paired with chemotherapy or targeted drugs. Chemotherapy and focussed radiotherapy (SABR) can help by releasing tumour antigens from a cancer cell and by inflaming the tumour, making it easier for immune cells to recognise the cancer and slow down tumour growth. Targeted drugs can cut off growth signals within a cancer cell, or cut off the tumour’s blood supply, again tipping the balance in favour of immune cells.

Immunotherapy is not automatically helpful for everyone. Its benefit often depends on molecular features, including:

• MSI / MMR status: MSI-high or mismatch-repair-deficient colorectal cancer and metastatic pancreatic cancer respond far better to immune checkpoint inhibitors than microsatellite-stable tumours.
• PD-L1 expression and tumour mutational burden: sometimes used to refine decisions, especially in rarer GI tumours.
• Underlying liver disease in HCC and detailed genomic profiling may reveal additional targeted options we can integrate with immunotherapy.

I routinely organise high-quality genomic testing so we know whether there is a realistic chance you will benefit from immunotherapy and what the safest, most effective treatment option is likely to be.

• Cancer type and stage.
• Exact tumour extent and other treatment options like SABR.
• Molecular profile (MSI/MMR status, PD-L1, key mutations).
• Liver function, autoimmune conditions and any previous treatments.

We use immunotherapy when evidence shows a meaningful chance of benefit – either increasing the likelihood of cure as part of a multimodal plan, or improving quality and length of life in advanced disease. It may be given alone or alongside chemotherapy, targeted therapy, radiotherapy or surgery.

Lines of therapy: If the cancer returns or becomes resistant, we move to the next most effective option. In MSI-high advanced bowel cancer, for example, immunotherapy may be used up front and followed by chemotherapy later if needed; in biliary cancer, chemo-immunotherapy may be first line, with targeted or second-line agents afterwards.

Response assessment: We schedule scans and track blood markers (such as CEA or AFP where relevant), but we interpret them through an ‘immunotherapy lens’. Sometimes responses are slower or look unusual at first (for example, inflammation before shrinkage). We take care not to stop helpful treatment too soon, while also switching promptly if it is clearly not working.

Biomarker profiling and re-testing: We confirm MSI/MMR status, PD-L1 where relevant, and key mutations. If your pathology was done many years ago or with limited testing, I may recommend re-biopsy or updated sequencing so we don’t miss an opportunity.

Oligoprogression: This is a situation where most of the cancer is responding to treatment, but a small number of tumours continue to grow. We can now target these resistant cancer cells using stereotactic radiotherapy; it helps to be under the care of a specialist with expertise in both drugs and radiation options.

Integrated care: Immunotherapy for pancreatic cancer and bowel cancer  works best when the rest of you is supported. Nutrition, exercise, sleep, stress, smoking cessation and alcohol moderation all influence how you tolerate treatment and how active your immune system can be against tumour cells. I believe in discussing these areas in at least as much detail as the drugs themselves, and I work closely with dietitians, physiotherapists and psychological support services where needed.

It’s normal to feel anxious about side effects, especially if you’ve read about severe reactions online. In reality, many people have only mild symptoms, and we now understand far more about how to prevent, spot and treat immune-related side effects early.

• Fatigue.
• Mild skin rash or itching.
• Achy joints or muscles.
• Slight changes in bowel habit.

However, because immunotherapy works by activating the immune system, it can sometimes cause inflammation in almost any organ. These ‘immune-related adverse events’ can range from mild to serious and may occur weeks to many months into treatment.

• Bowel / liver: diarrhoea or abdominal pain from colitis; abnormal liver tests or jaundice from hepatitis.
• Lungs: new or worsening cough and breathlessness from pneumonitis.
• Hormone glands: inflammation of the thyroid gland or hypothalamus can cause tiredness, weight change, feeling cold or hot, headaches, low blood pressure or mood changes. Some of these require long-term hormone tablets but are very manageable once diagnosed.
• Skin: widespread rash, blistering or severe itching.
• Kidneys and others: reduced urine output, swelling, or unusual neurological symptoms (such as persistent headache, confusion or weakness).

• Temperature at or above 38°C, shaking or shivering.
• New or rapidly worsening breathlessness or cough.
• Persistent or severe diarrhoea (especially if more than 4 extra bowel movements a day), blood in the stool or severe tummy pain.
• Yellowing of the eyes or skin, dark urine or very pale stools.
• Severe or rapidly spreading rash, blistering or peeling skin.
• Confusion, severe headache, visual changes or significant weakness.

Most immune-related problems are reversible if treated early with temporary treatment pauses, steroids and other supportive measures. Our goal is to keep you safe and well, and to allow immunotherapy to continue where it is still doing you good.

Safe and effective immunotherapy for metastatic bowel cancer, pancreatic cancer and liver cancer is about how treatment is coordinated as much as which drugs are chosen. With my team you receive:

• Rapid access to a consultation and, where appropriate, a prompt start date for treatment.
• A calm, well-staffed environment with oncology nurses and pharmacists experienced in delivering immunotherapy and spotting side effects early.
• Personal supervision. I remain closely involved, reviewing scans, blood tests and symptoms myself and adjusting treatment as needed.
• Joined-up support. We coordinate pathology and molecular testing, imaging, line insertion (if required), nutrition and psychological care so the whole programme fits together.
• 24/7 advice line for urgent concerns, plus easy access to in-person or video review when you need it.
• Clear information about costs whether you are insured or self-funding, so administration does not slow down your care.

Because immunotherapy can cause complex side effects that affect many organs, it is important that your team is comfortable guidelines and has rapid access to other specialists (for example, endocrinology, respiratory or hepatology) if needed. That is built into the way we work.