What is Lung Cancer?

Lung cancer is a type of cancer that begins in the lungs, which are responsible for supplying oxygen to the body and removing carbon dioxide. It occurs when cells in the lung grow uncontrollably, forming a tumour that can invade nearby tissues and spread (metastasize) to other parts of the body.

What are the symptoms of Lung Cancer?

Early Symptoms

• Persistent cough (that doesn’t go away or worsens)
• Changes in a chronic cough (e.g., smokers’ cough becoming different)
• Hoarseness

Common Symptoms

• Coughing up blood (hemoptysis) or rust-colored sputum
• Shortness of breath or wheezing
• Chest pain that worsens with deep breathing, coughing, or laughing
• Frequent lung infections (bronchitis or pneumonia)

Advanced Symptoms

• Unexplained weight loss
• Loss of appetite
• Fatigue and weakness
• Bone pain (if cancer spreads to bones)
• Headaches, dizziness, or seizures (if cancer spreads to brain)
• Swelling in face or neck (due to blocked blood flow from tumour pressure)

Paraneoplastic Symptoms (due to hormone-like substances produced by the tumour)

• High calcium levels (hypercalcemia)
• Muscle weakness
• Neurological symptom

How to detect Lung Cancer?

1. Screening for Early Detection

• Recommended for high-risk individuals (e.g., heavy smokers aged 50–80).
• Low-Dose Computed Tomography (LDCT) is the primary screening tool.
• Detects small nodules before symptoms appear.
• Reduces lung cancer mortality in high-risk groups.

2. Imaging Tests

• Chest X-ray
• Often the first step, but not sensitive enough for early detection.
  • CT Scan (Computed Tomography)
• Provides detailed images of lung tissue and detects smaller tumours.

3. Laboratory and Sputum Tests

• Sputum Cytology
• Examines mucus from the lungs under a microscope for cancer cells.
• Useful in detecting central lung tumours.

4. Tissue Biopsy (Definitive Diagnosis)

• Bronchoscopy with Biopsy

• A thin tube is inserted into the airways to collect tissue.
  • Needle Aspiration (CT-guided)
• Fine-needle biopsy through the chest wall.
  • Mediastinoscopy
• Surgical procedure to sample lymph nodes.
  • Surgical Biopsy (Thoracoscopy or Thoracotomy)
• Used when other methods are inconclusive.

5. Molecular & Genetic Testing

• Tests for mutations (e.g., EGFR, ALK, ROS1, KRAS) to guide targeted therapy.
• PD-L1 testing for immunotherapy decisions.

6. Staging Tests (After Diagnosis)

• PET Scan (Positron Emission Tomography)

• Detects cancer spread to other parts of the body.
  • MRI
• Checks brain or spinal cord involvement.
  • Bone Scan

Looks for bone metastases.

What are the available treatments for Lung Cancer?

1. Surgery (Mainly for Early-Stage NSCLC)

• Removes the tumour and surrounding tissue.
• Types:

• Lobectomy – Removal of one lobe (most common).
• Pneumonectomy – Removal of an entire lung.
• Segmentectomy/Wedge Resection – Partial removal (for small tumours or poor lung function).
  • Often combined with lymph node dissection

2. Radiation Therapy

• External Beam Radiation Therapy (EBRT) – Targets the tumour from outside the body.
• Stereotactic Body Radiation Therapy (SBRT) – High-dose, precise radiation for small tumours.
• Brachytherapy – Internal radiation for airway tumours.
• Used:

• When surgery is not possible.
• After surgery (adjuvant) to kill residual cells.

3. Chemotherapy

• Kills rapidly dividing cancer cells.
• Common drugs: Cisplatin, Carboplatin, Paclitaxel, Docetaxel, Pemetrexed.
• Used for:

• Advanced stages.
• Along with radiation (chemoradiation).
• After surgery (adjuvant) or before (neoadjuvant).

4. Targeted Therapy

• Blocks specific genetic mutations driving cancer growth.
• Examples:

• EGFR inhibitors: Erlotinib, Osimertinib
• ALK inhibitors: Crizotinib, Alectinib
• ROS1 inhibitors: Entrectinib
  • Requires molecular testing of the tumour.

5. Immunotherapy

• Boosts immune system to fight cancer.
• Checkpoint inhibitors:

• Pembrolizumab (Keytruda) – PD-L1 positive tumours.
• Nivolumab, Atezolizumab – Advanced or recurrent NSCLC.
  • Often used in advanced/metastatic stages.

6. Treatment for Small Cell Lung Cancer (SCLC)

• • Chemotherapy + Radiation (usually first-line): Cisplatin + Etoposide.
  • Prophylactic cranial irradiation (PCI): Prevents brain metastases.

• Immunotherapy (e.g., Atezolizumab) can be added in extensive-stage SCLC.

7. Palliative Care

• For advanced cases to control symptoms (pain, breathing issues).
• May include surgery, radiation, or medications for symptom relief.