Lung cancer can be diagnosed at an early stage with screening tests. It may be diagnosed incidentally in tests for another disease. If the diagnosis is made without symptoms, the treatment possibilities also increase. However, only 15% of patients can be diagnosed early.
In case of findings that are suspicious of the disease, different options, especially imaging tests and biopsy, will help to make the diagnosis.
One of the most important steps in the diagnosis of lung cancer is the evaluation of the patient in terms of risk factors. If the patient is thought to have one or more of the genetic or environmental risk factors, it is useful to be evaluated for lung cancer even if there are no signs and symptoms.
Imaging Tests:
- X-Ray (Chest X-ray): Lungs are visualized by means of X-rays. It is usually the first imaging test to suspect lung cancer. If a suspicious image is detected, advanced imaging methods are used. Lung tumors give a white-gray appearance. However, this image can also be seen in other lung diseases such as lung abscess. Therefore, it does not provide a definitive diagnosis.
- Computed Tomography: Using X-rays, many images of the lung tissue are taken in certain sections. In this way, information about the presence of the tumor, its location, whether it is solid or liquid, and its appearance is obtained. In the presence of tumor, biopsy is taken with the help of computed tomography. In addition, PET-CT can be taken for staging after the diagnosis of lung cancer.
- PET-CT: By administering a radioactive substance containing sugar, the contrast substance retention status of the lung, its surroundings and all body organs and tissues that may potentially spread is examined. Proximal and distant metastases of lung cancer are detected according to the contrast medium uptake. It is an important imaging test for lung cancer staging and therefore treatment options.
- Magnetic Resonance Imaging: MRI is mostly used for soft tissue imaging. It gives a detailed idea about the spread of lung cancer to soft tissue organs such as the brain and liver.
- Bone Scan: It can be used to show bone involvement in cases where PET-CT is not possible.
Bronchoscopy: In lung cancers, especially in the middle parts of the lung, a special instrument is entered through the bronchi. In this way, the lung tissue can be seen with the naked eye. A biopsy can be taken from the tumoral formation. In addition, ultrasonographic images can be taken from that area with an additional device to the bronchoscope. In addition to the lung tissue, surrounding lymph nodes can be visualized and a biopsy can be taken from them.
Mediastinoscopy: It is the examination of the thoracic cavity and the lymph nodes here by entering the back of the sternum with special instruments. When necessary, a biopsy is taken from the tissues here.
Thoracoscopy: The structures between the chest wall and the lung tissue are examined. It is used to take biopsy in cases where fine needle aspiration biopsy is not sufficient for diagnosis.
Biopsy: A biopsy is taken from the lung tissue with tumor by computed tomography, bronchoscopy, skin or other methods. A biopsy makes a definitive diagnosis. The type of lung cancer can be determined clearly. In addition, if it is taken, it also shows whether there is spread to the surrounding lymph tissues.
Thoracentesis: The filling of the space between the lung membranes makes it difficult for the patient to breathe. In this case, this space is entered with special tools. The liquid in the cavity is drained and samples are taken from this liquid and examined in the laboratory.
Spirometry: It is a procedure used to detect the amount of inhaled air and to measure the level of shortness of breath.
blood gases,
Blood tests: Detect signs of chest infection. Like complete blood count, biochemical tests. The functions of organs such as the liver, which are likely to spread from lung cancer, are also examined.
Genetic analysis: Genetic changes are seen in some types of cancer. These changes are looked at in genetic analysis. Such as KRAS gene, ALK gene, ROS1 gene, EGRF gene, BRAF gene, MET gene, NTRK gene in non-small cell lung cancers.
Lung Cancer Screening
Lung cancer screening can be done especially for people who have lung cancer in the family, use tobacco and tobacco products, and have occupational exposure to substances such as asbestos.
For this:
- Chest X-ray once a year,
- Sputum analysis once a year,
- Low-dose computed tomography can be performed.
The most accurate method that can be done is to implement an effective tobacco control program and quit smoking.