What is Lung Cancer?

Lung cancer is a type of cancer that starts in the lungs, the primary organs of the respiratory system responsible for oxygen exchange. It is one of the leading causes of cancer-related deaths worldwide. Lung cancer occurs when abnormal cells in the lungs grow uncontrollably, often forming a tumor. These cancerous cells can spread to other parts of the body if not treated early.

Types

Lung cancer is broadly classified into two main types based on how the cancer cells look under a microscope:

• Non-Small Cell Lung Cancer (NSCLC): This is the most common type, accounting for about 85% of cases. It includes subtypes such as:
  • Adenocarcinoma: Starts in cells that produce mucus.
  • Squamous Cell Carcinoma: Begins in the flat cells lining the airways.
  • Large Cell Carcinoma: A less common form that can occur in any part of the lung.
• Small Cell Lung Cancer (SCLC): A less common but more aggressive type, often associated with heavy smoking. It tends to spread quickly to other parts of the body.

Symptoms

Lung cancer symptoms may vary and often do not appear until the disease is advanced. Common symptoms include:

• Persistent cough that worsens over time
• Chest pain or discomfort
• Shortness of breath
• Wheezing
• Coughing up blood or rust-colored sputum
• Fatigue and unexplained weight loss
• Hoarseness
• Frequent respiratory infections, such as bronchitis or pneumonia

If you experience these symptoms, consult a healthcare provider for evaluation.

Causes and Risk Factors

The main cause of lung cancer is damage to lung cells, often linked to lifestyle or environmental factors. Risk factors include:

• Smoking: The leading cause of lung cancer, responsible for the majority of cases.
• Secondhand Smoke: Exposure to smoke from others increases the risk.
• Radon Gas: A naturally occurring radioactive gas that can accumulate in buildings.
• Exposure to Carcinogens: Workplace exposure to substances like asbestos, arsenic, and diesel exhaust.
• Family History: A genetic predisposition to lung cancer.
• Air Pollution: Prolonged exposure to polluted air can increase the risk.

Stages of Lung Cancer

Lung cancer is staged based on tumor size, lymph node involvement, and whether it has spread:

• Stage I: Cancer is confined to the lungs and has not spread to lymph nodes.
• Stage II: Cancer has spread to nearby lymph nodes or tissues.
• Stage III: Cancer has spread to lymph nodes in the middle of the chest or nearby structures.
• Stage IV: Cancer has spread to other parts of the body, such as the bones, brain, or liver.

Diagnosis

Diagnosing lung cancer involves several steps:

1. Imaging Tests

Tests such as chest X-rays, CT scans, or PET scans are used to identify abnormalities in the lungs.

2. Sputum Cytology

Examining mucus coughed up from the lungs can help detect cancer cells.

3. Biopsy

A sample of lung tissue is collected using methods like bronchoscopy, needle aspiration, or surgery for examination under a microscope.

4. Molecular Testing

Tests to identify genetic mutations or biomarkers in cancer cells can guide targeted therapy.

Treatment

Treatment for lung cancer depends on the type, stage, and patient health. Common options include:

1. Surgery

Surgical options aim to remove the tumor and may include:

• Lobectomy: Removal of one lobe of the lung.
• Pneumonectomy: Removal of an entire lung.
• Segmentectomy or Wedge Resection: Removal of a small portion of the lung.

2. Radiation Therapy

High-energy beams target and destroy cancer cells. It is often used in combination with surgery or chemotherapy.

3. Chemotherapy

Powerful drugs kill or slow the growth of cancer cells. It is often used for advanced stages or after surgery.

4. Targeted Therapy

Drugs like EGFR inhibitors or ALK inhibitors target specific genetic mutations in cancer cells.

5. Immunotherapy

Drugs that boost the immune system to attack cancer cells, such as checkpoint inhibitors, are effective for some lung cancers.

Prevention

Preventive measures can significantly reduce the risk of lung cancer:

• Avoid Smoking: The most effective way to prevent lung cancer is to never start smoking or quit if you do.
• Test for Radon: Test your home for radon and take corrective measures if necessary.
• Avoid Carcinogens: Follow workplace safety guidelines to limit exposure to harmful substances.
• Healthy Lifestyle: Maintain a balanced diet, exercise regularly, and limit alcohol consumption.
• Screening: High-risk individuals, such as smokers, should undergo regular lung cancer screenings with low-dose CT scans.

Conclusion

Lung cancer is a serious disease with significant health impacts. Awareness of risk factors, symptoms, and early detection through screening can improve outcomes. If you are at risk or experience symptoms, consult a healthcare provider promptly.