Diagnosing Lung Cancer

If lung cancer is suspected as a result of a screening procedure (CT, MRI or PET scan), a small piece of tissue from the lung must be examined under a microscope to look for cancer cells. Called a biopsy, this procedure can be performed in different ways. In some cases, the doctor passes a needle through the skin into the lungs to remove a small piece of tissue; this procedure is often called a needle biopsy.

In other cases, a biopsy may be done during a bronchoscopy. With the patient under sedation, the doctor inserts a small tube through the mouth or nose and into the lungs. The tube, which has a light, small camera and a surgical instrument on the end, allows the doctor to see inside the lung and remove a small tissue sample.

If cancer cells are found in the tissue sample, a genetic test may be performed. The information obtained from the test can help doctors choose the best treatment.

Pathologists (doctors who identify diseases by studying cells and tissues under a microscope) and geneticists (scientists with special training in the study of genes) can give your doctor the information he or she needs to tailor a treatment that will be most effective. These specialists can determine the distinct characteristics of each lung cancer: the tumor type (NSCLC or SCLC, for example); how far it has advanced (its stage); and the mutations (gene changes) that cause or “drive” the cancer.