What are the differences between emphysema and lung cancer?

Patient's question:

Dad has been coughing up a lot of phlegm and having difficulty breathing recently. He went to the hospital for a thorough examination, and the doctor said it was emphysema. I looked it up and found it's a rather serious condition. What's the difference between this and lung cancer? I'm truly heartbroken. It definitely won't develop into lung cancer, right? Boohoo

Doctor's answer:

Emphysema refers to a pathological state where the elasticity of the airways distal to the urethra is reduced, excessively expanded, dilated, and accompanied by a decrease in lung volume or destruction of the airway walls. Lung cancer is one of the most dangerous malignant tumors for human health and life. Emphysema is a chronic disease that can alleviate symptoms through treatment. However, lung cancer is a direct malignant tumor that threatens human life and must be treated promptly to avoid life-threatening risks.