Researchers reveal lung cancer can stay hidden for over 20 years

09 October 2014

Chest x-ray showing lung cancer.

Image: Chest x-ray showing lung cancer.

Scientists have discovered that lung cancers can lie dormant for over 20 years before suddenly turning into an aggressive form of the disease.

The team at Cancer Research UK's London Research Institute (LRI; now part of the Francis Crick Institute) studied lung cancers from seven patients - including smokers, ex-smokers and never smokers. They found that after the first genetic mistakes that cause the cancer, it can exist undetected for many years until new, additional, faults trigger rapid growth of the disease.

During this expansion there is a surge of different genetic faults appearing in separate areas of the tumour. Each distinct section evolves down different paths - meaning that every part of the tumour is genetically unique.

This research highlights the need for better ways to detect the disease earlier. Two-thirds of patients are diagnosed with advanced forms of lung cancer when treatments are less likely to be successful.

By revealing that lung cancers can lie dormant for many years the researchers hope this study will help improve early detection of the disease.

Professor Charles Swantonof LRI said: "Survival from lung cancer remains devastatingly low with many new targeted treatments making a limited impct on the disease. By understanding how it develops we've opened up the disease's evolutionary rule book in the hope that we can start to predict its next steps."

The study also highlighted the role of smoking in the development of lung cancer. Many of the early genetic faults are caused by smoking. But as the disease evolved these became less important with the majority of faults now caused by a new process generating mutations within the tumour controlled by a protein called APOBEC.

The wide variety of faults found within lung cancers explains why targeted treatments have had limited success. Attacking a particular genetic mistake identified by a biopsy in lung cancer will only be effective against those parts of the tumour with that fault, leaving other areas to thrive and take over.

Professor Nic Jones, Cancer Research UK's chief scientist, said: "This fascinating research highlights the need to find better ways to detect lung cancer earlier when it's still following just one evolutionary path. If we can nip the disease in the bud and treat it before it has started travelling down different evolutionary routes we could make a real difference in helping more people survive the disease."

The paper, Spatial and temporal diversity in genomic instability processes defines lung cancer evolution, is published in Science.

  • Lung cancers can lie dormant and hidden for more than 20 years before turning aggressive, according to new research from Cancer Research UK's London Research Institute. It's hoped that the findings will improve early detection of the disease.
  • Over 40,000 people are diagnosed with lung cancer each year and, despite some positive steps being made against the disease, it remains one of the biggest challenges in cancer research, with fewer than 10 per cent surviving for at least five years after diagnosis.
  • The research was jointly funded by Cancer Research UK and the Rosetrees Trust and run in collaboration with the Wellcome Trust Sanger Institute.