The stage of a cancer is a term used to describe its size and whether it has spread beyond its original site. Knowing the extent of the cancer and the grade (see below) helps the doctors to decide on the most appropriate treatment. The staging is different for small cell and for non-small cell cancers of the lung.

Small cell lung cancer

Small cell lung cancers are divided into just two stages. This is because small cell lung cancer often spreads outside the lung quite early on. Even if the doctor cannot see any spread of the cancer on your scans, it is likely that some cancer cells will have broken away and traveled through the bloodstream or lymph system. To be safe, small cell lung cancers are usually treated as though they have spread, whether any secondary cancer can be seen or not.

The two stages of small cell lung cancers are:

• Limited Disease - the cancer cells can be seen only in one lung, in nearby lymph nodes or in fluid around the lung (pleural effusion);
• Extensive Disease - the cancer has spread outside the lung within the chest area or to other parts of the body.

Non-small cell lung cancer

The four stages of Non-Small Cell Lung Cancer:

Stage 1 – This is a very localized cancer with no cancer in the lymph nodes.

Stage 2 – This cancer has spread to the lymph nodes close to the affected lung.

Stage 3 – This cancer has spread into the tissue around the lung near to where the cancer started. This can be into the chest wall, the covering of the lung (pleura), the middle of the chest or other lymph nodes.

Stage 4 – This cancer has spread to another part of the body.