It is any subtype or type of lung cancer. It occurs the cells in the lungs start to mutate and divide instead of dying off. The cause is unknown but smoking and radon exposure are the major risk factors for lung cancer. It is of two main types: non-small cell lung cancer (NSCLC) and small cell lung cancer (SCLC). Symptoms include worsening or persistent cough, coughing up mucus and blood, hoarseness, shortness of breath, wheezing, fatigue, persistent or frequent bronchial attacks, chest pain, headaches, unexplained weight loss, etc.

A second opinion can help in the proper diagnosis of the exact cause of the disease. Since the symptoms can resemble other lung conditions, a pulmonologist can provide clarification and confirmation of the disease. The doctor can also suggest alternative treatment options if surgery is not an option.