Cancer - Oncology

What Is Lung Cancer?

Lung cancer is an abnormal growth of cells in the tissue of the lungs that form large masses known as tumors. There are several types of lung cancer, and how a patient is treated depends on the type of lung cancer diagnosed and the stage of the cancer—the size, location, and if it has spread. Lung cancer causes more deaths in the United States than any other cancer, and the incidence of lung cancer in women. Although lung cancer historically has been difficult to treat, advances in both treatment and symptom management help make this an exciting and hopeful time for patients.

Types of Lung Cancer

There are two main types of lung cancer: non-small cell lung cancer, which is the most common and slow-growing form of the disease, and small cell lung cancer, which is a faster-growing form of the disease that is more likely to spread to other parts of the body.

Non-small cell lung cancers
Six types of non-small cell cancers are identified by the appearance of the cancer cells under a microscope:

  • Squamous cell carcinoma occurs in the thin, flat squamous cells.
  • Adenocarcinoma occurs in cells that secrete mucus.
  • Adenosquamous carcinoma occurs in cells that secrete mucus and are flat.
  • Large cell carcinoma occurs in cells that are abnormally large.
  • Undifferentiated carcinoma occurs in cells that do not look like normal cells and multiply uncontrollably.
  • Bronchoalveolar carcinoma could resemble a lung infection, and it is difficult to diagnose and may be complex to treat.

Small cell lung cancers
Three types of small cell lung cancer are:

  • Small cell carcinoma or oat cell cancer occurs in cells that are flat, small, shaped as an oval, and resemble oat grains.
  • Mixed small cell/large cell carcinoma occurs in cells that are a mix of small and large cancer cells.
  • Combined small cell carcinoma is small cell lung cancer combined with squamous and/or secreting cells.