Types of Lung Cancer

Lung cancer usually starts in the main airways of the lungs (the lining of the bronchi), but it can also begin in other areas of the respiratory system, including the trachea, bronchioles, or alveoli. Lung cancer is the leading cause of cancer death in both men and women. 

Nearly all lung cancers are carcinomas, which are cancers that begin in the lining or covering tissues of an organ. There are several types of lung cancer, and these types are broadly categorized by small cell lung cancer (SCLC) and non-small cell lung cancer (NSCLC). SCLC and NSCLC are treated differently, so it’s important to have an accurate diagnosis of which type of lung cancer you have before proceeding with treatment. 

Small cell lung cancer

Small cell lung cancer, also called “oat cell cancer” because it looks like oats under a microscope, usually makes up less than fifteen percent of all lung cancers. It tends to grow quickly, and it aggressively spreads to other parts of the body. Another type of small cell cancer is called combined small cell carcinoma. Most of the time, this type of lung cancer isn’t found until it has spread. SCLC is strongly associated with smoking.

SCLC has two stages:

  • Limited stage, when the cancer is only in one lung and maybe one lymph node near the lungs
  • Extensive stage, when the cancer is in both lungs and has spread to the pleura or to other organs in the body

Non-small cell lung cancer

Non-small cell lung cancer makes up about 85 percent of all lung cancers. There are three main types of NSCLC:

  • Adenocarcinomas – These are the most common type of NSCLC in the United States. They make up about 40 percent of all cases of lung cancer. It usually begins along the other edges of the lungs or under the lining of the bronchi. While smoking is a significant risk factor for adenocarcinomas, these types of lung tumors are also found in people who don’t smoke and never have. It is the most common type of lung cancer in people who have never smoked. Non-smoking women who get lung cancer often have this type of cancer. People who have this type of cancer tend to have a higher survival rate.
  • Squamous cell carcinomas – This type of cancer, also called epidermoid carcinoma, makes up for about 25 to 30 percent of all lung cancer. It is the most common type of lung cancer in men. They tend to begin in the middle of the chest in the bronchi, and it doesn’t usually spread as fast as other types of lung cancer.
  • Large cell carcinomas – Large cell carcinomas make up about 10 to 15 percent of all lung cancer. They usually begin along the outer edges of the lungs, and they have large, abnormal-looking cells. They tend to spread to the lymph nodes and other sites in the body that aren’t close to the lungs.
    • Undifferentiated carcinomas are a type of large cell carcinoma. They also have abnormal-looking cancer cells, and they tend to multiply quickly.

Doctors classify NSCLC by its size and how far it has spread. This is called staging. They stage it with the help of the TNM system. 

  • Tumor (T), which describes the size of the primary (original) tumor
  • Lymph node (N), which states whether the cancer has spread to the lymph nodes
  • Metastasis (M), which indicates whether cancer has spread to other parts of the body

Each letter in the TNM system also gets a number or the letter X. The higher the number, the larger the tumor is or the more it has spread. Doctors use an X when they cannot assess the tumor’s size or spread.

For example, someone may have a large tumor (T4) that has not spread to the lymph nodes (N0) or to other areas (M0). Or they may have a medium-sized tumor (T2) that has spread to one nearby lymph node (N1), but not to any other places in the body (M0). 

Once the TNM system has been used to assess the cancer, doctors can accurately stage it.

Other types of cancer that affects the lungs

There are other types of cancer that affect the lungs. Sometimes, cancer that started somewhere else will spread to the lungs. This is still lung cancer, but it’s considered secondary lung cancer, meaning the first site of cancer was somewhere else in the body. 

Malignant mesothelioma is another type of cancer that can affect the lungs. Malignant mesothelioma affects the mesothelium, which is a thin layer of tissue that covers most internal organs. It most commonly affects the pleura – the tissue surrounding the lungs. Mesothelioma in the lungs is called pleural mesothelioma. It spread aggressively, and it is difficult to cure.

The symptoms of pleural mesothelioma include:

  • Chest pain under the ribs
  • Coughing that tends to be painful
  • Shortness of breath
  • Lumps under the skin on the chest
  • Unexplained weight loss

Discover your treatment options at Beaumont

If doctors think you may have lung cancer, you can trust Beaumont to meet your treatment needs. Doctors at Beaumont detect more early stage cancers than any other hospital in Michigan. We use the most advanced treatments and the latest technology to offer patients individually targeted care. Our Lung Cancer Multidisciplinary Clinic at Beaumont Hospital, Troy offers you a highly trained and experienced team of cancer specialists.

Through Beaumont’s Multidisciplinary Lung Cancer program, we develop an individualized treatment plan based on your unique situation. Your doctor will work closely with you to develop the most effective treatment plan for you.