MRI-guided SABR for pancreatic cancer

Advanced pancreatic cancer can be a difficult disease, both because of where the pancreas sits — deep in the abdomen, surrounded by the stomach, bowel, liver and major blood vessels — and because many tumours are discovered at a stage where upfront surgery is not possible. Nevertheless, there are grounds for the cautious optimism that pancreatic cancer patients deserve, because treatments are improving all the time. One of the most important advances is MRI-guided SABR (stereotactic ablative radiotherapy): a highly precise, non-invasive treatment that uses real-time MRI imaging to target pancreatic tumours with millimetre accuracy.

SABR is transforming what is possible for people with every stage of pancreatic adenocarcinoma. It gives high rates of tumour control combined with excellent tolerability and the potential to extend life expectancy while preserving quality of life. At GenesisCare, the MRI-guided SABR service that I lead delivers this treatment using state-of-the-art MR-linac technology, allowing us to adapt the treatment each day and safely achieve higher doses than previously possible.

For patients with metastatic pancreatic cancer that has spread to other organs, SABR can also be useful treatment option. If there are up to five secondary tumours, carefully targeted ablative doses of radiation can often be used to eradicate them all. Whilst this isn’t a curative treatment, it can prolong the amount of time it takes for the cancer to get worse overall (what we call ‘disease progression’), and can also give a break from chemotherapy, which improves quality of life.

I have extensive experience of using advanced radiation therapy techniques to treat:

• Unresectable pancreatic cancer. Radiotherapy is used after or instead of chemotherapy to treat locally advanced disease – this includes both SABR and chemoradiotherapy.
• Borderline resectable tumours. Neoadjuvant (pre-operative) chemotherapy and radiotherapy can be used before attempted pancreatic resection surgery, in collaboration with surgical teams in Birmingham and London.
• Recurrent disease. SABR can eradicate a small area of cancer that grows back after a Whipples surgical resection where the tumour used to be.
• Resectable pancreatic cancer. In older people, or those with medical conditions where surgery would be too invasive and where chemotherapy treatment would be too hard on the body, radiotherapy controls tumour growth very well.
• Symptomatic tumours causing pain and other problems. Palliative radiotherapy and coeliac plexus radiosurgery can be used to help with unpleasant symptoms.
• Oligometastatic pancreatic cancer. When there is limited spread to other organs, SABR can eradicate secondary tumours and help delay disease progression.

Your case is always carefully assessed by a multidisciplinary team (MDT) including expert radiologists, other oncologists, and surgeons where needed. We consider all options including SABR, preoperative chemoradiation, and palliative radiotherapy.

If you’re exploring private pancreatic cancer treatment options, MRI-guided SABR represents a powerful and evidence-based addition to chemotherapy and surgery — and, for some, an option that keeps the disease controlled for longer than expected.

SABR (which is also referred to as stereotactic body radiation therapy, or SBRT) leverages advanced technology to focus the energy in X-rays on tumours, leading to their eradication (‘ablation’). The cancer cells are pushed beyond their ability to repair themselves, while the surrounding normal tissue mostly can. The radiation causes breaks in the DNA of pancreatic cancer cells and also damages the small blood vessels feeding the tumour, so over time the treated area tends to shrink, scar and lose its blood supply. Because SABR is given in just a few, powerful treatments, each dose is biologically much more intense than standard radiotherapy, which increases the chance of completely inactivating the targeted cancer cells. There’s also growing evidence that killing tumour cells in this focused, high-energy way can alert the immune system to their presence, sometimes helping your own defences recognise and attack cancer elsewhere in the body.

When it comes to pancreatic cancer,  the innovation comes when SABR is combined with MRI-guidance. The pancreas and surrounding organs move constantly as you breathe, digest, or even shift slightly on the treatment couch. The tumour often sits just millimetres from the stomach, bowel, duodenum, kidneys and bile duct. Delivering enough energy to control the tumour without harming these structures has historically been difficult. CT-guided radiotherapy cannot track this movement accurately enough to safely increase radiation dose. In fact, we often have to reduce the dose received by much of the tumour to prevent damage to normal tissues, and this can reduce overall effectiveness.

MRI-guided SABR addresses this problem by providing:

• Better anatomical visualisation
  MRI shows abdominal organs much more clearly than standard CT images, helping us distinguish tumour from normal tissue even when they are close together.
• Realtime imaging and motion management
  We can monitor tumour movement as you breathe and use ‘gating’ so that the radiation beam is only delivered when the target is in exactly the right place. This is particularly valuable for abdominal SABR, where tumours can move significantly with each breath.
• Daily adaptive planning
  With adaptive radiotherapy, we adjust the treatment plan on the day to account for changes in the tumour or nearby organs. This allows us to deliver a higher dose than conventional radiotherapy while respecting strict safety limits for sensitive organs.

Together, these features make it possible to deliver a higher radiation dose to more of the tumour than is possible on any other radiotherapy machine, and clinical trial data shows that this can translate into patient benefit.

Some hospitals offer IRE (irreversible electroporation) — a technique that uses electrical pulses to punch holes in tumour cells. While IRE has a role in selected patients, it has important limitations:

• Non-invasive: SABR requires no incisions, needles or anaesthetic. In the CROSSFIRE trial comparing IRE with SABR, general anaesthesia was required and most people needed three days in hospital after treatment.
• Complications: In the same trial, one in five (22%) patients had a severe complication of IRE whereas this happened in only 6% of the SABR group.
• Predictable: SABR delivers carefully planned treatment across the whole tumour and areas at risk of microscopic spread, whereas IRE results vary depending on electrode placement.
• Evidence base: Published studies on IRE show mixed results, whereas MRI-guided SABR has consistently demonstrated high rates of tumour control with low toxicity.

• Unrivalled expertise and clear, compassionate communication
• Consultation and full MDT review within a week
• Rapid access treatment pathway for insured and self-pay patients
• Coordinated care with your surgeon or chemotherapy team