Lung cancer is the uncontrolled cell growth in the tissues of the lung that develop into a malignant tumor. There are two main types, small cell lung cancer (SCLC) and non-small cell lung cancer (NSCLC). Lung cancer was rare before cigarette smoking existed. Now, it is the second most common cancer in people and is the leading cause of death due to cancer in the United States (25% of all cases). In 2021, the American Cancer Society estimates that there will be about 235,760 new cases of lung cancer diagnosed in the United States. The survival rate for lung cancer is better with early diagnosis and treatment. Lung cancer usually occurs in older people and is most common in smokers and former smokers. The more and longer you have smoked, the higher the risk. After quitting smoking, the risk lowers. Lung cancer is treatable if caught early and the risk of death from lung cancer goes up if treatment is delayed.
Lung cancer may not have any symptoms at all in the early stages. Once symptoms begin, cancer may have spread beyond the lungs. Early diagnosis and treatment are essential. If you have any of the below symptoms, see your doctor as soon as possible. These include:
- Cough that doesn’t clear up with time or treatment
- Recurrent infections (pneumonia, bronchitis)
- Shortness of breath
- Blood in phlegm
- Weight loss
- Chest pain with breathing
After cancer spreads, symptoms may include:
- Swollen lymph nodes
- Jaundice (yellow skin)
- Bone pain
Lung cancer can cause a few different syndromes and the symptoms of these are:
Horner syndrome. This occurs when the cancer is at the top of the lungs. Tumors put pressure on the nerve in the upper chest and neck causing:
- Shoulder pain
- Drooping eyelid
- One smaller pupil
- No sweating on the affected side of the face
Superior vena cava syndrome. The superior vena cava (SVC) is a major vein that carries blood from the head, neck, upper chest, and arms to the heart. This syndrome is usually associated with malignancies that compress the SVC causing a blockage or impairment of the flow of blood. This compression and obstruction compromise the flow of blood back to the heart, builds up pressure, and causes swelling in the upper chest, face, neck, and arms. A prominent sign of SVC syndrome is distended neck veins. Other symptoms include shortness of breath, dizziness, headaches, and loss of consciousness. This syndrome can be life-threatening.
Paraneoplastic syndromes. Tumors formed in lung cancer can produce hormonal substances that disrupt the hormone balance in the body. This imbalance can disrupt the anti-diuretic hormone in the kidneys causing too much salt loss in the body. It can also disrupt the adrenal glands and cause Cushing syndrome due to the overexposure of cortisol over time. Lung cancer can also raise blood calcium levels, cause blood clotting disorders and breast growth development in males.