Learning about NSCLC

Why and How NSCLC Begins

Many different "risk factors" (a risk factor is anything that increases a person's chance of developing cancer) can play a part in causing NSCLC. Smoking is by far the most common risk factor for NSCLC. However, many other things, such as asbestos, other environmental factors (such as radon), and family history can also increase the chances of developing NSCLC.

Most lung cancer starts in the lining of the bronchi, although it can also begin forming in other parts of the lung. First, there may be areas of precancerous changes in the lung. These changes are not a mass or tumor, can't be seen on an x-ray, and don't cause symptoms. As these areas develop into tumors, they may produce signals that cause new blood vessels to form nearby. These new blood vessels nourish the cancer cells, allowing a tumor to grow. Finally, the tumor becomes large enough to appear on an x-ray.

Once lung cancer occurs, cancer cells can break away and spread to other parts of the body. This is called metastasis. Unfortunately, lung cancer often spreads in this way before it is found. It's important to know that lung cancer often takes many years to develop, and most people do not show any symptoms early on.

Understanding the types of NSCLC

About 85% of all lung cancers are the non-small cell type. NSCLC is divided into 3 subtypes, which are characterized based on the type of cells found in the cancer. These subtypes may also differ in size, shape, and location:

  • Squamous cell carcinoma: tends to be found near the bronchus

  • Adenocarcinoma: usually found in the tissues of the lung

  • Large cell undifferentiated carcinoma: can start in any part of the lung and often grows and spreads quickly

The type of NSCLC that one has may make a difference in the type of treatment that the doctor recommends.

Tools

Chest X-ray

This is usually the first test because it can help detect a tumor.

CT and MRI scans

CT (computerized axial tomography) and MRI (magnetic resonance imaging) scans use computers to produce highly detailed pictures of the body. These images can show dimensions that help determine the size, shape, and location of the tumor. Both scans are helpful to see whether a tumor has spread from the lung to the lymph nodes or other parts of the body.

Bone scan

A small amount of harmless radioactive substance is injected into a vein. This is only done when there is pain in the bones, a sign that the cancer may have spread there.

Pet scans

PET (Positron Emission Tomography) scans are different from CT and MRI scans because they can distinguish between cells that are rapidly dividing—such as tumor cells. In addition to testing for lung cancer, PET scans can also be used as a follow-up to chest x-rays, CT scans, or MRI scans. This can determine if a tumor is cancerous as well as if and where it has spread.

Next: Stages of NSCLC