People suffering from a rare, hard-to-treat form of pancreatic cancer could be given targeted immunotherapies, new research suggests.

The results, by London’s Institute of Cancer Research (ICR), could help pick out those patients with pancreatic neuroendocrine cancer who are most likely to benefit from such treatment, a scientist involved in the work said.

Another said the findings are “hugely encouraging” in how they might help progress treatments for this rare form of the disease, by exposing its underlying biology.

Once this type of cancer – which starts in cells that produce hormones such as insulin – spreads, only one in four people will survive for more than five years, scientists said, adding that new treatment options are desperately needed.

The study, published in the journal Gut, used artificial intelligence (AI) to find that a particularly aggressive type of tumour can dodge the body’s immune system reaction by hijacking its response to viral infections.

Escaping the immune system’s reaction allows the cancer cells to grow and evolve, the researchers said.

Scientists at the ICR and The Royal Marsden NHS Foundation Trust, working with colleagues at the University and Hospital Trust of Verona in Italy, used AI and genetic analysis to study 207 tumour samples from patients with pancreatic neuroendocrine tumours for the levels of 600 immune-related genes.

Immunotherapy has transformed the outlook for a range of different cancer types.

The team also studied the presence of known targets for existing immunotherapies in four kinds of pancreatic neuroendocrine tumours.

Immunotherapy is a type of treatment which works by helping the body’s immune system to recognise and attack cancer cells.

Their findings – that the most aggressive type of tumour had the highest levels of an immune marker known as PD-L1 – suggest these tumours can be targeted with immunotherapies designed to take the brakes off the immune system so it can attack tumour cells, they said.

Dr Anguraj Sadanandam, team leader in systems and precision cancer medicine at the ICR, said: “Our new study offers an important basis from which to start developing new treatment strategies for a rare form of cancer, which starts in the hormone-producing cells of the pancreas.

“We found that there is a complex interplay between cancer and immune cells in the most aggressive type of pancreatic neuroendocrine tumours, which suggests immunotherapy could work for patients with this form of the disease.

“Our findings could help to pick out those patients most likely to benefit from immunotherapy – and we’re keen to translate our work into clinical trials to test the benefit of different immunotherapeutic strategies to tackle this hard-to-treat form of pancreatic cancer.”

Professor Paul Workman, chief executive of the ICR, said: “Pancreatic cancers have some of the poorest survival rates – so it’s hugely encouraging to see such an extensive study of the immune landscape of a rare form of pancreatic cancer, looking at the underlying biology to inform the best way forward in treating the disease.

“It’s fascinating to see a mechanism unveiled by which these tumours develop the activity of a highly distinct set of immune-related genes, as this could not only underlie the immune escape of these tumours, but also feed into their ability to evolve – one of the biggest challenges in cancer research and treatment today.

“Immunotherapy has transformed the outlook for a range of different cancer types, and I look forward to seeing these new findings progress to clinical trials, which might lead to a more personalised way of treating people with pancreatic neuroendocrine tumours.”