🫁 Lung Cancer

What is Lung Cancer?

Lung cancer is a type of cancer that starts in the lungs — the two spongy organs in your chest that take in oxygen and release carbon dioxide when you breathe. It is one of the most commonly diagnosed cancers worldwide, and is also one of the leading causes of cancer-related death in the Philippines.

The good news is that early detection and advanced treatments — including targeted therapies — have greatly improved outcomes for many patients, even those diagnosed at later stages.

Types of Lung Cancer

There are two main types of lung cancer, and treatment decisions depend greatly on which type you have:

Non-Small Cell Lung Cancer (NSCLC)

This is the most common type, accounting for about 85% of all lung cancers. It includes three subtypes:

• Adenocarcinoma — The most common subtype, often found in the outer parts of the lung. Common in non-smokers and younger patients.
• Squamous Cell Carcinoma — Usually found in the central part of the lung, near the airways. More often linked to smoking.
• Large Cell Carcinoma — A less common type that can appear in any part of the lung and tends to grow and spread quickly.

Small Cell Lung Cancer (SCLC)

This type accounts for about 15% of lung cancers. It grows and spreads faster than NSCLC, but it is also more sensitive to chemotherapy and radiation therapy. It is almost always caused by smoking.

Common Symptoms

Lung cancer often does not cause symptoms in its early stages. When symptoms do appear, they may include:

• A new cough that doesn't go away, or a worsening chronic cough
• Coughing up blood — even a small amount
• Shortness of breath
• Chest pain that worsens with deep breathing, coughing, or laughing
• Hoarseness or changes in your voice
• Unexplained weight loss and loss of appetite
• Fatigue and weakness
• Recurring respiratory infections (pneumonia, bronchitis)

Diagnosis: How Lung Cancer is Found

Diagnosis typically involves several steps:

• Imaging tests — Chest X-ray, CT scan (computed tomography), or PET scan to identify suspicious areas
• Biopsy — Removal of a small tissue sample to be examined under a microscope. This confirms whether cancer is present and what type it is.
• Molecular/genetic testing — Tests on the cancer tissue to look for specific gene mutations (e.g., EGFR, ALK, ROS1, PD-L1). This is especially important for NSCLC patients, as it determines whether targeted therapy is an option.
• Bronchoscopy — A thin tube passed through the mouth or nose to view the airways and collect tissue samples.

Staging: How Far Has It Spread?

Lung cancer is staged from Stage I (localised) to Stage IV (spread to other organs). The stage helps guide treatment decisions.

• Stage I–II: Cancer is in or near the lung. Surgery may be an option to remove the tumour.
• Stage III: Cancer has spread to lymph nodes in the chest. Treatment often combines chemotherapy and radiation.
• Stage IV: Cancer has spread to other organs (e.g., brain, bones, liver). Targeted therapy, immunotherapy, and chemotherapy are the main treatment approaches.

Treatment Options

Surgery

For early-stage NSCLC, surgery to remove the tumour and nearby tissue offers the best chance of cure. Types include lobectomy (removing a lobe of the lung) and pneumonectomy (removing an entire lung).

Chemotherapy

Drugs given orally or intravenously to kill cancer cells throughout the body. Often used in combination with surgery or radiation, or as the main treatment for advanced-stage cancer.

Targeted Therapy

If genetic testing shows specific mutations in your cancer cells (e.g., EGFR mutation), targeted therapy drugs can specifically attack those mutated cells — often with fewer side effects than traditional chemotherapy. Examples include Erlotinib, Gefitinib, and Osimertinib.

Immunotherapy

Medicines that help your own immune system recognise and destroy cancer cells. Drugs such as pembrolizumab (Keytruda) have shown strong results in certain lung cancer patients.

Radiation Therapy

High-energy beams directed at the tumour to destroy cancer cells. Can be used alone, with chemotherapy, or after surgery to kill remaining cells.

Questions to Ask Your Doctor

• What type and stage of lung cancer do I have?
• Has my tumour been tested for genetic mutations (EGFR, ALK, ROS1)?
• Am I a candidate for surgery, targeted therapy, or immunotherapy?
• What are the goals of treatment — cure, or managing the disease?
• What clinical trials might be available for my type of cancer?
• What are the expected side effects of the recommended treatment?