Lung Cancer

Lung cancer begins when cells in the lungs start growing uncontrollably. It is one of the most common cancers worldwide and a leading cause of cancer-related deaths — but outcomes are improving dramatically thanks to new treatments and earlier detection.

There are two main types of lung cancer, and the type matters because it determines your treatment:

• Non-Small Cell Lung Cancer (NSCLC): Accounts for about 85% of all lung cancers. This includes subtypes like adenocarcinoma (most common, especially in non-smokers), squamous cell carcinoma, and large cell carcinoma.
• Small Cell Lung Cancer (SCLC): Makes up about 15% of cases. It grows and spreads faster than NSCLC and is almost always linked to heavy smoking.

Understanding the causes and risk factors for lung cancer can help you take steps to protect yourself and your family. Some risk factors can be controlled, while others cannot.

• Smoking: The #1 cause of lung cancer, responsible for about 80% of lung cancer deaths. The risk increases with the number of cigarettes smoked per day and the number of years of smoking. Bidis and hookah carry similar risks.
• Secondhand Smoke: Breathing in other people's smoke increases your lung cancer risk by 20-30%. There is no safe level of exposure to secondhand smoke.
• Air Pollution: Long-term exposure to polluted air — especially fine particulate matter (PM2.5) from traffic, factories, and cooking with solid fuels — is a recognized risk factor.
• Occupational Exposure: Working with asbestos, radon, arsenic, diesel exhaust, or certain chemicals increases risk. Radon is a colorless, odorless gas that can accumulate in homes built on certain types of soil.
• Family History: Having a parent or sibling with lung cancer increases your risk, even if you don't smoke. Genetic factors may make some people more susceptible.
• Previous Lung Disease: Conditions like COPD (chronic obstructive pulmonary disease), pulmonary fibrosis, or tuberculosis can increase lung cancer risk.

Lung cancer often shows no symptoms in its early stages, which is why it's sometimes called a "silent" cancer. When symptoms do appear, they are often mistaken for other common conditions. Pay attention to:

• A persistent cough that doesn't go away or gets worse over time — especially if it's different from your usual cough.
• Coughing up blood (hemoptysis) — even a small amount should be evaluated immediately.
• Chest pain that is often worse with deep breathing, coughing, or laughing.
• Shortness of breath — feeling winded during activities that previously didn't bother you.
• Unexplained weight loss — losing weight without trying, especially 5 kg or more.
• Recurring respiratory infections — frequent bouts of pneumonia or bronchitis may indicate a tumor blocking an airway.
• Hoarseness — a change in your voice that persists for more than two weeks.

If lung cancer is suspected, your doctor will order a series of tests to confirm the diagnosis and understand the type and extent of the cancer. Here's what to expect:

• CT Scan (Computed Tomography): A detailed X-ray that creates cross-sectional images of your lungs. This is usually the first imaging test and can detect tumors as small as a few millimeters.
• PET Scan: Uses a small amount of radioactive sugar to highlight areas of high metabolic activity — cancer cells "light up" because they use more sugar than normal cells. Helps determine if cancer has spread.
• Biopsy: A small sample of the tumor is taken and examined under a microscope. This is the only way to confirm lung cancer. It can be done through a bronchoscopy, needle biopsy, or surgery.
• Molecular Testing: Modern lung cancer treatment depends heavily on identifying specific genetic changes in your tumor. Tests for mutations like EGFR, ALK, ROS1, BRAF, KRAS, and markers like PD-L1 help your oncologist choose the most targeted and effective treatment.

Staging describes how far the cancer has grown and spread. It's one of the most important factors in choosing the right treatment. Lung cancer is staged from I to IV:

Lung cancer treatment has evolved dramatically in recent years. Your treatment plan depends on the type of lung cancer, its stage, molecular profile, and your overall health.

• Surgery: The best option for early-stage NSCLC. The surgeon may remove a small section (wedge resection), a lobe (lobectomy), or an entire lung (pneumonectomy). Minimally invasive (VATS) surgery reduces recovery time.
• Chemotherapy: Uses drugs to kill cancer cells. It's a standard treatment for SCLC and is often combined with other therapies for NSCLC. Given in cycles to allow recovery between treatments.
• Radiation Therapy: Uses high-energy beams to target and destroy cancer cells. Can be used alone for patients who can't have surgery, or in combination with chemotherapy. SBRT (stereotactic body radiation therapy) can precisely target small tumors.
• Targeted Therapy: If your tumor has specific mutations like EGFR or ALK, targeted drugs (such as osimertinib or alectinib) can block those mutations. These are often oral tablets with fewer side effects than chemotherapy and can be remarkably effective.
• Immunotherapy: Drugs like pembrolizumab (Keytruda) and nivolumab (Opdivo) help your immune system recognize and attack cancer. Immunotherapy has transformed the outlook for many patients with advanced lung cancer, sometimes leading to long-lasting responses.
• Combination Treatments: Many patients receive a combination of these approaches. For example, chemotherapy + immunotherapy is now a standard first-line treatment for advanced NSCLC without targetable mutations.