Two-thirds of those diagnosed with lung cancer are seniors. However, people can actually walk around with lung cancer for as long as 20 years before they exhibit signs and know they have it.
While the majority of people who are diagnosed with cancer in their lungs are over 65, they may actually have signs and genetic factors present in their 40s. Recent research funded by the Rosetrees Trust and Cancer Research UK shows that genes that foster the development of lung cancer may lie dormant in someone for two decades before they turn aggressive, establish noticeable symptoms and metastasize.
Lung cancer has a devastatingly low survival rate compared to other forms of cancer. This led the researchers to search for the disease’s evolution to determine why. Part of the answer turned out to be how deeply embedded the disease is before people even seek a diagnosis.
Researchers looked deeply into the genetic mistakes that resulted in the formation of a lung cancer tumor in seven lung cancer patients. The group included smokers, former smokers, and even in those who have never smoked.
While the researchers found smoking does instigate more of the early genetic faults, they determined that the tumors do not develop quickly. They can lay dormant for years before suddenly progressing. Furthermore, as the cancer cell growth progressed and the person aged, there were different types of genetic faults that appeared in different areas, causing different cancer cells, even within one tumor, to progress differently. This led the team to establish that each part of the tumor has some unique genetic differences.
The research showed that early genetic markers reflected the impact smoking has in the development of lung cancer. However, the earlier genetic faults became less important as the disease progressed and new ones were responsible for later mutations in the tumor. This seems to imply that smokers are more likely to develop early signs of cancer, but the playing field levels off as people age and smoking becomes less important in the disease’s development.
Researchers hope that by establishing that lung cancer can lie dormant for many years, cancer experts will be able to develop better and timelier detection methods. Noting the need to detect lung cancer much earlier on its evolutionary path, Cancer Research UK’s chief scientist, Professor Nic Jones, commented that, if research scientists can nip the disease in the bud and prevent it from starting down different evolutionary routes, the researchers believe there will be a real difference in helping more of those diagnosed with lung cancer to survive.
While the percentage of people who smoke tobacco has declined markedly in the U.S., the American Cancer Society estimates that more than 224,000 new cases of lung cancer will be diagnosed this year. More than 159,000 people will die from the disease.
Now that researchers have shown that people can have lung cancer for 20 years before they even know it, it becomes apparent that early detection can make a difference. At this point, less than 10 percent of lung cancer patients survive five years after their diagnosis, which may be 20 years after the first cancer cells begin growing, according to the research. Being able to determine the genetic faults within lung cancer earlier may make treatment easier and more effective.
By Dyanne Weiss