Lung cancer is caused by the cells of the lungs dividing and multiplying at a faster rate than normal resulting in a cellular mass known as a tumour. These tumours can be restricted to the first few layers of cells, in this instance they are known as benign. If the tumour spreads to the surrounding tissues or organs it will then become a malignant or cancerous tumour. Cancerous cells from this tumour can break off and travel to other parts of the body where they will multiply, this process is known as metastasis.
Lung cancer survival rate refers to the percentage of people who survive the disease for a specific time period after being diagnosed, the time period usually being 5 years. Survival rates have increased in the lasts 40 years due to advancements in medicine, however mortality rates are still high. There are several stages of lung cancer which medical professionals use to identify the severity of the disease and the stage of its progression. The survival rates vary for each stage of the disease. In non-small cell lung cancer there are 5 stages; stage 0, stage 1, stage 2, stage 3 and stage 4. The 5 year survival rate for level 0 lung cancer is between 70% and 80% compared to stage 4 lung cancer which is less than 2%. In small cell lung cancer the 5 year survival rates are a lot lower; between 15% and 30% in limited stage lung cancer where the disease is confined to one lung, the mediastinum and nearby lymph nodes, and 0%-2% in extended stage lung cancer where the disease has spread to other parts of the body. Lung cancer survival also depends on the overall health of the patient and their reaction to the treatment given.
How early the cancer is found impacts greatly on the chances of survival. Lung cancer can be terminal and about 60% of people die within one year of being diagnosed. However some people do survive and go on to live for many years.