Lung Cancer: Tests After Diagnosis

After a diagnosis of lung cancer, you will likely have other tests. These tests help your healthcare providers learn more about your cancer. They can help show if the cancer has grown into nearby areas or spread to other parts of the body. The test results help your healthcare providers decide the best ways to treat the cancer. If you have any questions about these or other tests, be sure to talk with your healthcare team.

The tests you may have can include:

• Lab tests of biopsy or surgery samples

• CT scan

• MRI

• Positron emission tomography (PET) scan

• Bone scan

• Endobronchial or esophageal ultrasound

• Mediastinoscopy or mediastinotomy

• Bone marrow biopsy

Lab tests of biopsy or surgery samples

Lung cancer is usually diagnosed by removing a sample of a tumor during a biopsy. If non-small cell lung cancer (NSCLC) is diagnosed, special lab tests may be done on the biopsy samples to see if the cancer cells have certain gene changes. These tests can help show whether certain types of cancer medicines are likely to work to treat the cancer.

Imaging tests

CT scan

During a CT scan X-rays are used to scan a part of the body such as the chest or abdomen to create detailed pictures. When you have lung cancer, these pictures help your doctor see where the cancer is in your chest. They also show if the cancer has spread to nearby lymph nodes or to other organs such as the liver or adrenal glands. The adrenal glands are small glands that rest on top of each kidney. 

MRI

An MRI uses magnets, radio waves, and a computer to create detailed pictures of the inside of your body. An MRI may be used to find out if cancer has spread to your chest or brain. If it has, an MRI can also show the size of it and how far it has spread. Your doctor may also ask for an MRI if the results of an X-ray or CT scan aren't clear. In some cases, you are injected with a contrast dye before getting the scan. 

PET scan

A PET scan can give the doctor a better idea of whether an abnormal area seen on a CT scan or other imaging test is a tumor. If you have already been diagnosed with cancer, your doctor may use this test to look for spread of the cancer to lymph nodes or other parts of the body. A PET scan can also help if your doctor thinks the cancer may have spread, but doesn't know where. Because the PET scans your whole body, your doctor may order this scan instead of ordering multiple X-rays of different places on your body. The picture is not as detailed as a CT scan, but it can be used along with a CT scan to look for tumors. 

Bone scan

A bone scan is similar to a PET scan, but it uses a different radioactive substance that marks changes in bones. The bones may change because the cancer has spread there. This test is done mainly when your doctor thinks the cancer may have spread to your bones. Regardless of which type of lung cancer you have, you may not need a bone scan if you have already had a PET scan. This is because both test can often show the same type of results.

Procedures to look for cancer spread 

Endobronchial or esophageal ultrasound

These tests can be used to look for cancer that has spread to lymph nodes or other problems in the area between the lungs (mediastinum). 

For an endobronchial ultrasound, a bronchoscope is fitted with an ultrasound transducer at its tip and is passed down into the windpipe. The transducer gives off sound waves and picks up the echoes as they bounce off body tissues. The echoes are converted by a computer into an image on a computer screen. The transducer can be pointed in different directions to look at lymph nodes and other structures in the mediastinum. If the doctor sees suspicious areas such as enlarged lymph nodes, he or she will pass a hollow needle through the bronchoscope to get biopsy samples of them. The samples are then sent to a lab to be looked at under a microscope.

A similar test, known as endoscopic esophageal ultrasound, can also be used to look at lymph nodes in the mediastinum. But for this test, an endoscope is passed down the esophagus instead of the windpipe.

Mediastinoscopy or mediastinotomy

These tests can also be used to look at the lymph nodes between the lungs. Although an imaging test such as a CT scan may show if you have enlarged lymph nodes, the doctor needs to find out if they have cancer in them. 

These tests are done by a surgeon. Your doctor may make a small cut in the front of your neck for a mediastinoscopy. Less often, your doctor may make a small cut in your chest between your ribs for a mediastinotomy. This lets him or her see different sets of lymph nodes. The doctor then uses a lighted scope with a small video camera on the end to look at the center of your chest and the lymph nodes there. The doctor can also use special instruments passed down the scope to remove some tissue. The cells removed from the lymph nodes are sent to the lab to be checked for cancer.

Bone marrow biopsy

This test is not used nearly as often as some of the others. But you may need it if you have small cell lung cancer (SCLC) and the doctor wants to see if the cancer has spread to the bone marrow.

Working with your healthcare provider

Your healthcare provider will talk with you about which tests you will have. Make sure to get ready for the tests as instructed. Ask questions and talk about any concerns you have.