The lungs are an essential part of the respiratory system. The respiratory system consists of a pair of lungs that also have different parts. The right lung has three lobes, and the left lung has two. A thin layer called the pleura to protect the lungs. Cells in the lungs do tend to change and can grow or stop behaving normally. Some of these cells can grow into benign, non-cancerous tumors or malignant tumors. These cells can destroy the nearby tissue and can also spread to other parts of the body, causing lung cancer.
Lung cancers can be primary and secondary, depending on the location that it starts. Primary tumors in the lungs start locally, and secondary ones start in another part of the body and spread to the lungs. It is also further divided into non-small cell lung cancer and small cell lung cancer, depending on the appearance of the cancer cells under the microscope.
Common risk factors
- Smoking
- Passive smoking
- Exposure to radiation
- Radon
- Occupational exposure to certain chemicals
- Asbestos
- Air pollution
- Prior history of lung cancer
Signs and symptoms
Most common symptoms of lung cancer are:
- Wheezing
- Shortness of breath
- Cough
- Weight loss
- Fatigue
- Weakness
- Recurrent chest infections like bronchitis
- A build-up of fluid around the lungs
- Chest pain
- Blood in the mucus when coughed up from the lungs
Diagnostic tests
Imaging tests
Imaging tests are essential when it comes to diagnosis as these imaging tests enable doctors to understand the location of cancer, to see how far it has spread, to see if treatment is working and understanding of the cancer is coming back.
The various imaging tests conducted are listed below:
- Computed tomography (CT)
- Positron emission tomography (PET) scan
Other procedures used in the diagnosis.
- Sputum cytology
- Bronchoscopy
- Mediastinoscopy
- Fine needle biopsy (FNAC)
- Biopsy
What is non-small cell lung cancer?
Non-small cell lung cancer constitutes about 80% of lung cancer cases are further classified into four different types:
- Adenocarcinoma
Adenocarcinoma forms in the mucus-producing surface epithelium and is the most common type of cancer in women and non-smokers.
- Bronchi alveolar carcinoma
This type of cancer forms near the air sacs of the lungs
- Squamous cell carcinoma
Squamous cell carcinoma forms in the lining of the bronchial tubes, which is strongly associated with smoking tobacco.
- Large cell carcinoma
Large cell carcinomas form near the outer edges or surface of the lungs. This type of cancer is rare.
What is small cell lung cancer?
Small cell lung cancer (SCLC), also known as small cell carcinoma, is a type of cancer that is characterized by small cells that multiply and form large tumors that spread. This kind of cancer mostly occurs in smokers and spreads fast.
