Warnings, based on a new study, have been issued that lung cancer may remain dormant for 20 years before it turns into an aggressive form of the disease.
The initial genetic mutations responsible for the cancer may not be detected for up to 20 years before other faults trigger the cancer cells to start replicating. During this time there is a boost of various genetic faults which appear in different parts of the tumour. Each section goes down different pathways, which implies that every section of the tumour is genetically unique.
Researchers hope that this new discovery will result in earlier detection of the disease.
Two-thirds of lung cancer patients receive diagnoses at a point when available treatments are likely to be unsuccessful.
More than 40000 people are diagnosed with lung cancer annually, but less than 10% survive for a period of more than five years after being diagnosed.
Professor Charles Swanton from Cancer Research UK’s London Research Institute and the UCL Cancer Institute, said lung cancer survival rates remain extremely low and many of the new targeted treatments have a limited effect on the disease.
He said that by starting to understand the development process of the disease, its evolutionary rule book has been opened in the hope that it will become possible to predict its next move.
The study involved the examination of lung cancers from seven patients, including ex-smokers, those who had never smoked and smokers.
The results of the study placed focus on the role smoking has in the development of the disease.
It was found that many of the initial genetic faults are attributed to smoking. However, as the disease evolves, this loses importance as most of the faults caused by a new process which generates mutations within the tumour, are controlled by a protein named APOBEC.
The wide spectrum of faults discovered within lung cancers offers an explanation as to why targeted treatments have had stunted success. By treating a particular genetic error which has been identified by a biopsy will render it affective against those particular sections of the tumour housing that particular fault, but leaves the other sections to grow and assimilate.
The chief scientist at Cancer Research UK, Professor Nic Jones, said this interesting research places focus on the requirement to find more effective methods of detection of the disease, at the point when it is still on a single evolutionary path.
He said that if the disease can be treated prior to going down different evolutionary routes, a difference could be made in the survival rates.
Based on this study, Cancer Research UK has offered funding for a study named TRACERx. This will involve studying hundreds of lung cancers and its evolution to determine how it mutates, adapts and becomes treatment-resistant.
Image Credit: Yale Rosen