Imaging Tests
One of the most common methods used to diagnose lung cancer is through imaging tests. X-rays are often the first step in imaging tests to detect any abnormalities in the lungs. CT scans provide more detailed images of the lungs and can help determine the size and location of any tumors. MRI scans may be used to get a clearer picture of the lungs and surrounding tissues. PET scans can show areas of increased metabolic activity in the body, which can indicate the presence of cancerous cells.
Biopsy
A biopsy is often necessary to confirm a lung cancer diagnosis. There are different types of biopsies, including needle biopsies, bronchoscopy, and surgical biopsies. During a biopsy, a small sample of tissue is removed from the lung and examined under a microscope for any cancerous cells. The results of the biopsy can help determine the type of lung cancer and its stage.
Sputum Cytology
Sputum cytology is a non-invasive test that examines the cells in a patient's sputum (phlegm). This test can sometimes detect cancerous cells in the lungs, especially in cases where the tumor is located near an airway. While sputum cytology is less invasive than a biopsy, it is not always as accurate in diagnosing lung cancer.
Blood Tests
Blood tests may be used to look for certain substances that are associated with lung cancer. For example, measuring levels of carcinoembryonic antigen (CEA) in the blood can sometimes indicate the presence of lung cancer. Other blood tests may check for genetic mutations or biomarkers that can help diagnose or monitor lung cancer.