Lung Cancer

Lung cancer is a disease caused by uncontrolled cell growth in the lungs. Normally, cells divide and die in a regulated cycle, but mutations in their DNA can cause them to multiply uncontrollably, forming tumors that interfere with lung function. Lung cancer typically originates in the airways (bronchi or bronchioles) or the small air sacs (alveoli). When cancer spreads from other organs to the lungs, it is referred to as metastatic cancer.

Early-stage lung cancer often has no symptoms, and when symptoms do appear, they can resemble less serious conditions. Common signs include:

• Persistent or worsening cough
• Shortness of breath
• Chest pain or discomfort
• Wheezing
• Coughing up blood
• Hoarseness
• Loss of appetite and unexplained weight loss
• Fatigue
• Shoulder pain or swelling in the face and neck
• Rare syndromes such as Horner’s syndrome

Lung cancer occurs when genetic mutations alter the instructions in a cell’s DNA, causing cells to grow and divide uncontrollably. These cancerous cells can form tumors, invade healthy tissue, and spread to other organs (metastasis). Smoking is the leading cause, but lung cancer can also develop in non-smokers due to genetic factors or environmental exposures.

• Non-Small Cell Lung Cancer (NSCLC): The most common type, accounting for over 80% of cases. Includes adenocarcinoma, squamous cell carcinoma, and less common variants.
• Small Cell Lung Cancer (SCLC): A fast-growing, aggressive cancer often diagnosed after it has spread.
• Other Lung-Related Cancers: Lymphomas, sarcomas, and pleural mesothelioma, which are treated differently and not classified as lung cancer.

Several factors increase the likelihood of developing lung cancer:

• Smoking: The primary risk factor; smokers are 10–30 times more likely to develop lung cancer.
• Exposure to toxins: Asbestos, radon, arsenic, radiation, and industrial chemicals.
• Age: Risk rises significantly after age 40.
• Family history: Genetic predisposition increases risk even in non-smokers.

Diagnosis involves physical exams, imaging, and tissue sampling:

Biopsy methods: Fine-needle aspiration, bronchoscopy, thoracentesis, mediastinoscopy, thoracoscopy.
Imaging tests: CT scan, MRI, PET scan, and advanced technologies like Photon-Counting Detector CT combined with AI for enhanced accuracy.

Treatment depends on cancer type, stage, and patient health:

Surgery: Removes tumors and lymph nodes; mainly for early-stage NSCLC.
Radiotherapy: High-energy X-rays target cancer cells; not used for metastatic cases.
Chemotherapy: Drugs to kill or slow cancer cell growth.
Targeted Therapy: Focuses on cancer cells with minimal impact on healthy cells.
Combination Therapy: Often the most effective approach, tailored by oncologists.

Side Effects: Vary by treatment type and may include fatigue, nausea, hair loss, skin irritation, and organ-specific complications.