Types of Lung Cancer

January 24, 2025

This page was reviewed under our medical and editorial policy by Jyoti Malhotra, M.D., M.P.H., associate professor, Department of Medical Oncology & Therapeutics Research, City of Hope^® Orange County Lennar Foundation Cancer Center; and Jae Y. Kim, M.D., associate professor, Division of Thoracic Surgery, Department of Surgery, City of Hope Cancer Center Duarte

Lung cancer begins when cells in the lungs start to grow uncontrollably. In some cases, lung cancer may spread to lymph nodes or other parts of the body. The two main types of lung cancer are small cell lung cancer (SCLC) and non-small cell lung cancer (NSCLC). There are different subtypes of SCLC and NSCLC, as well as a handful of other types of cancerous lung tumors that are neither SCLC or NSCLC.

Non-Small Cell Lung Cancer

Non-small cell lung cancer, also known as NSCLC, is the most common type of lung cancer. About 8 in 10 lung cancers are this type. NSCLC has several subtypes, including the following.

Adenocarcinoma: This type of cancer begins in the lungs’ epithelial cells, which make mucus, and is the most common type of NSCLC.

Squamous cell carcinoma: This type of lung cancer affects the thin, flat cells in the lining of the airways, which are known as squamous cells.

Large cell undifferentiated carcinoma: This is a fast-growing cancer that may start in any part of the lung.

Other less common types of NSCLC include the following.

Sarcomatoid carcinoma: This type of lung cancer has features of carcinoma (cancer that starts in the skin or in the lining or covering of organs) and sarcoma (cancer of the supportive or connective tissue, such as bone, cartilage, fat, muscle or blood vessels).

Adenosquamous carcinoma: This type of cancer affects both squamous cells and cells of glandular tissue.

Pancoast: This is a rare tumor that grows in the top part of the lungs and may affect the surrounding structures.

Small Cell Lung Cancer

Small cell lung cancer, also known as SCLC, makes up about 10% to 15% of all lung cancers. It tends to grow and spread quickly. There are two main types of SCLC, which derive their names from how the cancer cells look under a microscope.

Small cell carcinoma: Also known as “oat cell” cancer, this is the most common type of SCLC. It is fast-growing and may spread quickly to other parts of the body.

Combined small cell carcinoma: This rare type of lung cancer has features of both SCLC and NSCLC contained within the same tumor.

Other Types of Lung Tumors

Besides NSCLC and SCLC, there are other types of lung tumors that are less common. These include the following.

Lung carcinoid tumors: Also known as lung carcinoids or neuroendocrine tumors, these are slow-growing tumors that make up less than 5% of all lung cancers.

Salivary gland-type lung carcinoma: This is a slow-growing tumor of the central airway that starts in the mucus-secreting (submucosal) glands.

Large cell neuroendocrine carcinoma: This is a rare, fast-growing tumor with features of SCLC and NSCLC.

Mediastinal tumors: These are rare and begin growing in the space between the lungs. They may be slow-growing or aggressive, depending on the organs involved.

Mesothelioma: This is a rare, fast-growing tumor that may start in the lining around the lungs. Most cases are caused by exposure to asbestos.