The relationship between asbestos exposure and lung cancer has been well established. Smokers who have had asbestos exposure are at even greater risk of developing lung cancer. Recently, a program to help detect lung cancer early in patients at risk has been accepted. The patients in the high risk group are those 55 to 75 years of age and who have smoked at least 30 pack years (the number of packs smoked daily times the number of years smoked). Patients who have had asbestos exposure are not part of this risk group but we generally keep them under surveillance. Findings on x-ray help detect the presence of asbestos-related lung disease.
One of the most common findings in patients exposed knowingly, or unknowingly, to asbestos is thickening of the inner lining of the chest wall. This thickening is called a plaque. The plaques may be present even when the lung tissue looks normal on CT scanning. The relationship of these plaques to the development of lung cancer has been controversial.
Over 5400 men in France exposed to asbestos were studied. It appears that plaques are an independent risk factor for lung cancer in asbestos exposed patients. That means that, regardless of other factors, having plaques increases your risk for developing lung cancer. This finding tells you that if you have been told you have pleural plaques, or if you have had asbestos exposure, you should have some annual surveillance to detect lung cancer early when treatment is most effective.