Lung Cancer Diagnosis
Lung Cancer Diagnosis
Lung cancer is diagnosed with the help of the following tests:
- Blood test
- Chest X-ray
- PET-CT scan (Positron Emission Tomography Computerized Tomography); is carried out if CT-scan shows an early-stage lung cancer
- Bronchoscopy and biopsy (use of a small tube that is passed through the mouth to examine lungs and take a sample of cells from there)
- Other biopsies: such as mediastinoscopy, thoracoscopy, or fine-needle aspiration
CT Scan (Computerized tomography)
A CT (computerized tomography) scan uses an x-ray and a computer screen to show the detailed structure of internal organs, bones and blood vessels. Patients are given an injection containing a dye, which helps show the structure of the lung more clearly. They then lie on their back while a cylindrical machine rotates to conduct the scan. The procedure is painless and takes 10-30 minutes.
If the CT scan indicates that cancer may be present at an early stage, patients may be referred to do a PET scan
PET – (Positron Emission Tomography)
A PET scan, meaning a positron emission tomography scan, helps to show how certain parts of the body are functioning. Patients are injected with a radioactive substance while lying in a PET scanner. The procedure lasts 30-60 minutes and is painless.
If the PET scan shows that the possibility of cancer in the central part of the chest, a bronchoscopy may be next.
Bronchoscopy and Biopsy
A bronchoscopy allows the removal of a sample of cells from the lung.
During the procedure, a tube called a bronchoscope is passed through the nose into the passage to the lung. The bronchoscope can examine the lung tissue and take a sample of cells (biopsy). This procedure may be slightly painful, but usually the patient is given a mild sedative and local anesthetic to numb the throat. The procedure takes just a few minutes.
A pathologist will analyze the cells from the biopsy under a microscope and determine if the cells are malignant (cancerous) or not.
Mediastinoscopy: A surgical procedure used to look at the mediastinum (the space behind the breastbone in the middle of the chest), which contains the heart and its great vessels, and lymph nodes.
Thoracoscopy: A surgical procedure that allows the healthcare provider to see the outside of the lungs, the space between them and the chest wall.
Fine-needle aspiration: A type of biopsy in which a thin needle is inserted into abnormal-looking tissue to collect a sample.
The type of tests ordered for the diagnosis of lung cancer depends on the patient’s symptoms, physicians’ judgment, standard guidelines, and availability of resources.
Examination of the cells to determine the extent to which it has spread. Lung cancers fall into two broad categories.
Non-Small-Cell Lung Cancer
This cancer tends to grow slowly and takes a longer time to develop than small cell lung cancer:
Stage I: Cancer is small and contained within the lungs. It has not yet spread beyond the lung tissue.
- Stage IA means that the size of the tumor is 3 centimeters (cm) or less.
- Stage IB means that the size of the tumor is more than 3 cm but less than 4 cm.
Stage II: Cancer has spread beyond the lung tissue
- Stage IIA means that the tumor is larger than 4 cm but does not exceed 5 cm in size. Moreover, no lymph nodes are affected at this stage.
- Stage IIB means that the tumor does not exceed 5 cm in size, but it has spread to the lymph nodes. A tumor of size of more than 5 cm that has not spread to any lymph nodes is also labelled as stage IIB.
Stage III: Cancer has spread to the lymph nodes but not to other distant parts of the body. At this stage, the tumor is quite difficult to remove.
Stage IV: Cancer has spread to both lungs, other parts of the body such as bone, liver, and brain, or has caused fluid containing cancer cells to build up around the heart and lungs. Non-small-cell lung cancer is more likely to spread to the liver, bones, brain, and adrenal glands.
- Stage IVA means that the spread of cancer is within the chest and/or just one area outside the chest.
- Stage IVB means that cancer has spread outside the chest and also involves one or more than one organ.
Small-Cell Lung Cancer
There are only 2 stages of small-cell lung cancer:
Limited Disease Stage: The cancer has not spread outside the lung
Extensive Disease Stage: The cancer has spread beyond the lung