Lung Cancer Types

What are the Major Types of Lung Cancer?

diagram of the lungs
What are the different types of lung cancer?. istockphoto.com

Types of Lung Cancer

There are several lung cancer types, and it is important for your oncologist to determine which form of lung cancer you have in order to choose the best treatment options for you. The treatment choices, as well as the prognosis for a lung cancer, can vary widely depending on both the particular cancer type and the stage at which it is diagnosed. The majority of lung cancers are classified as either non-small cell lung cancer or small cell lung cancer, which get their names because of the appearance of the cancer cells under a microscope.

Uncommon forms of lung cancer include neuroendocrine tumors such as carcioid. Cancers such as sarcomas and lymphomas may occur in the lungs.

Cancers of other tissues, such as breast cancer, may spread to the lungs. When this is the case, the cancer is named based on the tissue in which it began. For example, breast cancer which has spread to the lung would be called "breast cancer metastatic to the lungs" instead of lung cancer.

Non-Small Cell Lung Cancers:

Non-small cell lung cancer accounts for 80 percent of lung cancers. These are further broken down into 3 types:

Adenocarcinoma of the Lung

Up to 50 percent of non-small cell lung cancers are considered adenocarcinomas. This type of lung cancer is often seen in non-smokers and is the lung cancer type most commonly found in women. Non-small cell lung cancer usually begins in the periphery (outer parts) of the lungs, and it can be present for a long time before it is diagnosed.

 

Squamous Cell Carcinoma (Epidermoid Carcinoma)

Thirty percent of non-small cell lung cancers are squamous cell carcinomas. This lung cancer type usually starts in the bronchial tubes in the central part of the lungs and can cause symptoms early on, especially hemoptysis (coughing up blood).

Squamous cell carcinoma used to be the most common form of lung cancer, but its incidence appears to have decreased since filtered cigarettes became available and smoke is inhaled more deeply into the lungs (the region where adenocarcinoma begins).

Large Cell Carcinoma

Large cell carcinoma is the least common form of non-small cell lung cancer, responsible for about 10 percent of cases. It is named for the appearance of large round cells when examined under the microscope. Large cell carcinoma often occurs in the outer regions of the lungs and tends to grow rapidly

Small Cell Lung Cancer

Small cell lung cancer accounts for 20 percent of lung cancers, and it is the lung cancer type linked most strongly with smoking. Small cell lung cancer usually grows in the central areas of the lungs, and most people have few symptoms until just before they are diagnosed. This lung cancer type usually grows and spreads very rapidly, with the majority of people having inoperable cancer at the time of diagnosis.

Even though most of these cancers cannot be cured by surgery, small cell lung cancer often responds well to chemotherapy and radiation.

Mesothelioma

Mesothelioma is not actually cancer that develops in the lungs, but rather begins in the mesothelium, a membrane that surrounds the lungs. Only about 2,000 cases are diagnosed per year in the United States, but the incidence is increasing worldwide. Most cases of mesothelioma are due to exposure to asbestos on the job.

Lung Carcinoid Tumors (Bronchial Carcinoids)

Carcinoid tumors account for up to 5 percent of lung cancers, but not all lung carcinoid tumors are malignant (cancerous). These tumors are made up of cells called neuroendocrine cells. In contrast to other lung cancer types, carcinoid tumors are usually found in younger people, often people under the age of 40, and are not related to smoking. Most carcinoid tumors grow fairly slowly and can often be removed with surgery.

Secondary Lung Cancer (Metastatic Cancer to the Lungs)

Cancer that has spread to the lungs from other regions of the body, for example, the breast, is called secondary lung cancer. In this example, the cancer begins in breast tissue, not lung tissue, and would be referred to as breast cancer metastatic to the lungs, rather than lung cancer.

Rare Tumors That Can Present in the Lungs

Tumors that begin in tissue other lung tissue are occasionally found in the lungs. Some tumors that can present in the lungs include sarcomas, hamartomas, and lymphomas.

Sources:

National Cancer Institute. Non-Small Cell Lung Cancer Treatment PDQ - Health Professional Version. 07/07/16. http://www.cancer.gov/types/lung/hp/non-small-cell-lung-treatment-pdq

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