Q: How Does Lung Cancer Spread?
A:When lung cancers are still localized, five-year relative survival rates are right around 53 percent. However, once the cancer has spread to distant areas of the body, the patient’s chances of survival drop to around 4 percent. Simply put, the spread of lung cancer can mean the difference between life and death for those battling the disease. A cancer actually spreads from one location in the body to another by a process on the cellular level.
Lung cancers often originate within a growth or tumor. Through the process of metastasis, cells from the tumor eventually break off and then travel through the body via the bloodstream or lymphatic system. Once this occurs, the cancerous cells can affect distant tissues and organs and new cancers can develop. These would be completely separate cancers, however, and would be categorized differently.
In that situation, the original lung cancer would be called the primary cancer. Any cancers which develop in distant regions of the body from the metastasis of the lung cancer would be referred to as secondary cancers. Once lung cancer has spread to these distant organs or tissues, treatment can become increasingly difficult. Cancers diagnosed in the most advanced stage have already undergone metastasis.