A lung nodule is a mass of tissue located in the lungs. Though about 40% of these growths are benign, they can be cancerous, especially in older people and smokers. Many people with this condition don't have any symptoms, though some do have wheezing, shortness of breath, or a persistent cough.edical professionals can examine chest X-rays for indications of lung nodules. Smokers are at a serious risk of developing lung nodules. A lung nodule is a mass of tissue located in the lungs. Cancerous lung nodules may be removed through a surgical procedure.