​

What is lung cancer? 

​

Lung cancer is the uncontrolled growth of abnormal cells in one or both lungs. These abnormal cells do not carry out the functions of normal lung cells and do not develop into healthy lung tissue. Tumors that are cancerous are called malignant and noncancerous tumors are called benign.

• Cancer is always named for the place where it starts. Lung cancer originates in the lungs. When cancer cells spread from one organ to another, they are called metastases.  So, when lung cancer metastasizes (spreads) to any other place, it’s still lung cancer.

• Treatment for cancer that has spread is primarily based on where it started (the primary cancer site).  Treatment for lung cancer is also based on the lung cancer type.
   

Types of lung cancer
 

There are 2 main types of lung cancer, non-small cell (NSCLC) and small cell (SCLC). These types of lung cancer grow differently and are treated differently. Non-small cell lung cancer is more common than small cell lung cancer. According to The Association of Clinical Oncologists (ASCO), 85% of new cases of lung cancer are Non-Small Cell Lung Cancer.

 

Non-Small Cell Lung Cancer
There are 3 primary subtypes of NSCLC:

• Adenocarcinoma is the most common and usually appears in the peripheral or the cells that form the lining of the lungs. It may be found in those with a history of smoking, but it is the most common type found in non-smokers, women and younger patients.

• Squamous cell carcinoma usually occur in the center of the lungs in one of the bronchi.  It frequently spreads to the lymph nodes and is strongly associated with smoking. 

• Large cell carcinoma occur anywhere in the lung tissue and grow the most rapidly of the three types.  It is not as common as the other types of NSCLC.
   

Small Cell Lung Cancer

• About 10% to 15% of all lung cancers are Small Cell Lung Cancer.  Almost always seen in the bronchi (the airways in the center of the chest) and is rarely found in non-smokers.

• This type of lung cancer tends to grow and spread faster than NSCLC. About 70% of people with SCLC will have cancer that has already spread at the time they are diagnosed. 
   

Mesothelioma

• Is a cancer of the lining of organs in the chest including the lungs, abdomen, heart and chest.  It is associated with exposure to asbestos.

​

Along with the main types of lung cancer, other tumors can occur in the lungs.

• Lung carcinoid tumors - Carcinoid tumors of the lung account for fewer than 5% of lung tumors. Most of these grow slowly.

• Other lung tumors: Other types of lung cancer such as adenoid cystic carcinomas, lymphomas, and sarcomas, as well as benign lung tumors such as hamartomas are rare.