80% of cases of lung cancer are of the non-small cell type. Of these, only about 20% are at a sufficiently early stage to be potentially curable1, and more than 50% have already spread outside the lungs by the time the cancer is diagnosed2. For locally advanced disease that has not metastasised, complete resection can result in 5 year survival rates as high as 20-30%1.
Small cell lung cancer is usually in an advanced stage at diagnosis, and is treated with radiotherapy and chemotherapy.
As with other cancers, it is important from a medicolegal viewpoint to understand that most lung carcinomas and their metastases have been growing for years before they are clinically detectable3. Even with Computed Tomography (CT) a lung cancer must grow to 7-10 mm before it is visible: at this stage it contains about a billion cells and has already undergone about 30 doublings4.
Chest radiographs miss at least 20% of early lung cancers4a. Annual chest radiography with or without examination of sputum for cancer cells does not result in earlier diagnosis or improved mortality5,6. However, annual low dose helical CT is under investigation as a cost-effective screening method7.
The commonest presentation of early lung cancer is as a small solitary nodule. Nevertheless, such nodules usually prove not to be cancers, particularly if there is evidence that they have not enlarged for a year or two, and management is usually based on CT appearances with or without Fine Needle Biopsy8.
Surgery should be performed by surgeons who are operating frequently for lung cancer.