Other Diagnostic Tests

For diagnosis and staging purposes, tests other than common laboratory tests, imaging studies, and biopsy may be ordered.

Immunohistochemistry
This test uses antibodies to check for certain antigens in a sample of tissue. The antibody is usually linked to a radioactive substance or dye that causes the tissue to light up under a microscope. This type of test may be used to differentiate between cancer types.

Genomic Testing
Genomic testing, also called molecular, biomarker, or tumor testing, looks for certain changes, or mutations, in the tumor's DNA, as well as the levels of specific proteins present in the tumor. This information can be helpful in evaluating treatment options.

Sputum Cytology
In this test, a microscope is used to check for cancer cells in the sputum, which is the mucus coughed up from the lungs. This test is more common in places where there are no pulmonologists available.

Light and Electron Microscopy
This is a laboratory test in which cells in a sample of tissue are viewed under regular and high-powered microscopes to look for certain changes in the cells. This test is uncommon.