Detecting and Diagnosing Lung Cancer

It’s well known that treating cancer as early as possible makes it easier to treat for the best outcome. Lung cancer, however, doesn’t often show signs until the disease has progressed to a later stage. For those who are at the highest risk of developing lung cancer, a screening process has been developed to try to identify it earlier, when treatment is easier.

What is Lung Cancer Screening, and Who Qualifies?

People at high risk of lung cancer should have their lungs screened every year with a low-dose CT scan (LDCT) — especially since lung cancer symptoms don’t always appear until it is at a later stage. 

Lung cancer screenings are recommended for people who:

• Are between ages 50 to 80 years old and in good health,
  and
• Currently smoke or have quit in the past 15 years,
  and
• Have at least a 20-pack-year smoking history. (This is the number of packs of cigarettes per day multiplied by the number of years smoked. For example, someone who smoked 2 packs a day for 10 years [2 x 10 = 20] has 20 pack-years of smoking, as does a person who smoked 1 pack a day for 20 years [1 x 20 = 20].)

In addition, it’s important that people who are going to be screened:

• Receive counseling to quit smoking if they currently smoke,
  and
• Have been told by their doctor about the possible benefits, limits, and harms of screening with LDCT scans,
  and
• Can go to a center with experience in lung cancer screening and treatment.

Read about the American Cancer Society’s guidelines regarding lung cancer screening.

Tests For Lung Cancer 

A variety of tests are used to detect, diagnose, and even stage lung cancer or determine if cancer has spread (metastasized) to another part of the body.

Often, a biopsy is the only sure way for your doctor to know if an area of the body has cancer. In a biopsy, your doctor takes a small sample of tissue for testing in a laboratory. If a biopsy is not possible, he or she may suggest other tests to help make a diagnosis.

Your doctor may consider these factors when choosing a diagnostic test:

• Size, location, and type of cancer suspected
• Your signs and symptoms
• Your age and general health
• The results of earlier medical tests

In addition to a physical exam and questions about your family health history, the following tests may be used to diagnose and stage the different types of lung cancer, including small cell lung cancer (SCLC) and non-small cell lung cancer (NSCLC). 

Tests to Detect and Stage Small Cell Lung Cancer

• Chest x-ray: An x-ray of the organs and bones inside the chest. An x-ray is a type of energy beam that can go through the body and onto film, making a picture of areas inside the body.
• CT Scan (CAT scan) of the brain, chest, and abdomen: A series of detailed pictures of areas inside the body, taken from different angles. The pictures are made by a computer linked to an x-ray machine. A dye may be injected into a vein or swallowed to help the organs or tissues show more clearly. This procedure is also called computed tomography, computerized tomography, or computerized axial tomography.
• PET Scan (positron emission tomography scan): A small amount of radioactive glucose (sugar) is injected into a vein, which aims to find malignant tumor cells in the body. The PET scanner rotates around the body and makes a picture of where glucose is being used in the body. Malignant tumor cells show up brighter in the picture because they are more active and take up more glucose than do normal cells.
• Sputum Cytology: A microscope is used to check for cancer cells in the sputum (mucus coughed up from the lungs).
• Bronchoscopy: Uses a bronchoscope, which is a thin, tube-like instrument with a light and a lens for viewing, that is inserted through the nose or mouth into the trachea and lungs to look inside the trachea and large airways in the lung for abnormal areas. A bronchoscope may also have a tool to remove tissue samples, which are checked under a microscope for signs of cancer.
• Fine-needle aspiration (FNA) biopsy of the lung: A CT scan, ultrasound, or other imaging procedure is used to locate the abnormal tissue or fluid in the lung, and then a small incision may be made in the skin where the biopsy needle is inserted into the abnormal tissue or fluid. A sample is removed with the needle and sent to the laboratory. A pathologist then views the sample under a microscope to look for cancer cells. A chest x-ray is performed afterward to ensure that no air is leaking from the lung into the chest.
• Thoracoscopy: A surgical procedure to check for abnormal areas by looking at the organs inside the chest. A thoracoscope is a thin, tube-like instrument with a light and a lens for viewing. Typically, an incision (cut) is made between two ribs to insert a thoracoscope into the chest for viewing or for using a tool to remove tissue or lymph node samples that are then checked under a microscope for signs of cancer.
  
  In some cases, this procedure is used to remove part of the esophagus or lung. If certain tissues, organs, or lymph nodes can’t be reached, a thoracotomy may involve a larger incision between the ribs to open the chest.
   
• Thoracentesis uses a needle to remove fluid from the space between the lining of the chest and the lung. A pathologist views the fluid under a microscope to look for cancer cells.

Tests to Detect and Stage Non-Small Cell Lung Cancer

• Laboratory tests: Includes testing samples of tissue, blood, urine, or other substances in the body. These tests help to diagnose disease, plan and check treatment, or monitor the disease over time.
• MRI (magnetic resonance imaging): A procedure that uses a magnet, radio waves, and a computer to make a series of detailed pictures of areas inside the body, such as the brain. This procedure is also called nuclear magnetic resonance imaging (NMRI).
• Radionuclide bone scan: Used to check if there are rapidly dividing cells, such as cancer cells, in the bone. A very small amount of radioactive material is injected into a vein and travels through the bloodstream. The radioactive material collects in the bones and is detected by a scanner.
• Endoscopic ultrasound (EUS): A procedure in which an endoscope is inserted into the body. A probe at the end of the endoscope is used to bounce high-energy sound waves (ultrasound) off internal tissues or organs and make echoes. The echoes form a picture of body tissues called a sonogram. This procedure is also called endosonography. EUS may be used to guide fine needle aspiration (FNA) biopsy of the lung, lymph nodes, or other areas.

At Virginia Oncology Associates, we understand that receiving a diagnosis of lung cancer can be overwhelming. Our lung cancer specialists are dedicated to providing patients with personalized care and the latest treatment options.