Stages of small cell lung cancer

The TNM staging of small cell lung cancer is the same as for non small cell lung cancer. But in practice, small cell lung cancers are often divided into just two groups. This is because small cell lung cancer often spreads quite early on. Even if the doctor cannot see any spread on your scans, it is likely that some cancer cells will have broken away and travelled through the bloodstream or lymphatic system. To be safe, doctors often prefer to treat small cell lung cancers as if they have spread, whether they can see any secondary cancer or not.

The two stages of small cell lung cancers are limited disease and extensive disease.

• Limited disease is cancer that can only be seen in one lung, in nearby lymph nodes or in fluid around the lung (pleural effusion)
• Extensive disease is cancer that has spread outside the lung to the chest or to other parts of the body

Surgery is not usually used to treat small cell cancer, except in very early cases. Your doctor will probably suggest chemotherapy with or without radiotherapy. The scans and tests you have done at first will be used later to see how well you are responding to treatment.

Pleural effusion

A pleural effusion is fluid between the membranes covering the outside of the lungs - the pleura. The fluid takes up space and makes it impossible for the lung to expand fully when you breathe. If there is a lot of fluid, it can make you very breathless.

The fluid has to be checked for cancer cells. If it does have cancer cells, it is called a malignant pleural effusion and will affect the stage of your cancer. Occasionally, someone with lung cancer has fluid around the lung but the fluid doesn't contain cancer cells. If there are no cancer cells, it doesn't count towards your lung cancer stage.

In small cell lung cancer, pleural effusion containing cancer cells, but with no other signs of cancer spread is often classified as limited disease. But not all doctors agree on this. Some think that a pleural effusion may be better grouped as extensive disease.

In non small cell lung cancer, pleural effusion containing cancer cells means your cancer is considered to be at least stage 3B.

Your doctor will decide which stage you are by taking a number of different factors into account and pleural effusion is just one of these.