Lung cancer is a serious disease characterized by the abnormal and uncontrolled growth of cells in the lungs, which are responsible for the body's oxygen intake and carbon dioxide expulsion. This condition typically begins with genetic mutations in the cells lining the airways, disrupting the normal function of lung tissue. Common symptoms of lung cancer may include a persistent cough lasting at least three weeks, shortness of breath, unexplained weight loss, constant fatigue, chest pain felt when breathing or coughing, hoarseness, recurrent bouts of pneumonia or bronchitis, shoulder pain, swelling in the face or neck, difficulty swallowing, and palpable lumps around the neck or collarbone.