Oral cancer is often found in long-term smokers, but it can also affect non-smokers due to alcohol consumption, human papillomavirus (HPV), or poor oral hygiene.

Mr. Phuong, 65, a 40-year smoker, now suffers from severe systemic vascular narrowing, facing a high risk of heart attack and sudden death.

Smoking damages the respiratory tract, often manifesting as a persistent cough with phlegm and potentially an early sign of lung cancer.

My father doesn't smoke, but recently he's been coughing in the mornings and feeling slightly tired. Has the doctor diagnosed chronic obstructive pulmonary disease? What are the signs of lung damage in non-smokers? (Hoai Vy, Hanoi)

I smoke a few cigarettes when I'm stressed or meeting friends. Am I at risk of lung disease? Recently, I've had a persistent cough for about two weeks. (Hai Nam, Ho Chi Minh City)