What is lung cancer?
The lungs are the most important part of the respiratory system. The respiratory system consists of a pair of lungs that also have different parts. The right lung has 3 lobes and the left lung has two lobes. The lungs are protected by a thin layer called the pleura. Cells in the lungs do have a tendency to change and can grow or stop behaving normally. Some of these cells can grow into benign tumors that are non-cancerous or into malignant tumors. These cells can destroy the nearby tissue and can also spread to other parts of the body. This is known as lung cancer.
It can be seen as primary and secondary depending on the location that it starts from. Primary tumors in the lungs start locally and secondary ones starts in another part if the body and spreads 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.
- Passive smoking
- Exposure to radiation
- Occupational exposure to certain chemicals
- Air pollution
- Prior history of lung cancer
Most common symptoms of lung cancer are:
- Shortness of breath
- Weight loss
- Recurrent chest infections like bronchitis
- Build up of fluid around the lungs
- Chest pain
- Blood in the mucus when coughed up from the lungs
Imaging tests are important when it comes to diagnosis as these imaging tests enable doctors to understand the location of the cancer, to see how far it has spread, to see if treatment is working and to understand if the cancer is coming back.
They various imaging tests conducted are listed below:
- Computed tomography (CT)
- Positron emission tomography (PET) scan
Other procedures used in the diagnosis.
- Sputum cytology
- Fine needle biopsy (FNAC)
What is non-small cell lung cancer?
Non-small cell lung cancer constitutes about 80% of the lung cancer cases are are further classified into four different types:
Adenocarcinoma forms in the mucus-producing surface epithelium and is the most common type of cancer that is seen 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. This 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 less common.
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 is often seen in smokers. This is an aggressive kind of which spreads fastly.