Determining the type of lung cancer is the first step in deciding the best treatment. There are two main types of lung cancer: non-small cell lung cancer (NSCLC) and small cell lung cancer (SCLC). Several subtypes exist within these categories, and there are also a few other relatively rare types.
Some tumors contain cells that are both SCLC and a form of NSCLC (often large cell). Doctors need to know the type of cancer you have to determine the best treatment for lung cancer, because each type requires a different approach.
- 1 Non-small cell lung cancer
- 2 Adenocarcinoma
- 3 Squamous cell carcinoma
- 4 Large cell carcinoma
- 5 Small cell lung cancer
- 6 What is the most aggressive type of lung cancer?
Non-small cell lung cancer
Non-small cell lung cancer (NSCLC) is the most common type of lung cancer, accounting for 80-85% of all cases.
There are different types of NSCLC, which arise from different types of lung cells, but the most commonly diagnosed are:
– Squamous cell carcinoma
– Large cell carcinoma
– It usually develops in cells in the outer part of the lung that normally secrete substances such as mucus.
– This cancer occurs mainly in smokers, but it is also the most common lung cancer in non-smokers.
– It is more common in women than in men.
– If you are young and are diagnosed with lung cancer, the most likely type is adenocarcinoma.
– It tends to be diagnosed earlier than other types of lung cancer.
There is a rare subset of adenocarcinoma that begins in the alveoli (the tiny air sacs of the lungs), called adenocarcinoma in situ (AIS), previously known as bronchioloalveolar carcinoma. AIS tumors account for approximately 3% of lung cancer diagnoses. People with AIS generally have a better prognosis (outlook) than those with other types of lung cancer.
Squamous cell carcinoma
About 30% of all lung cancers are squamous cell carcinomas. This type of lung cancer develops in the thin, flat cells that line the airways, most often in the middle part of the lung, near a main airway. Squamous cell carcinomas are linked to smoking.
Large cell carcinoma
Large cell carcinoma accounts for about 9% of all lung cancers. This cancer can occur in any part of the lung. It usually grows and spreads quickly, making it difficult to treat. One type of large cell carcinoma, called large cell neuroendocrine carcinoma, is the fastest growing NSCLC and looks similar to small cell carcinoma.
Other subtypes of NSCLC
Other NSCLC subtypes include adenosquamous carcinoma and sarcomatoid carcinoma. These are much less common forms of lung cancer.
Small cell lung cancer
Small cell lung cancer (SCLC) accounts for approximately 15 to 20% of lung cancers. This cancer is a type of neuroendocrine tumor containing cells that are smaller than most other cancer cells. SCLC develops rapidly, and about 70% of people with it are not diagnosed until after the cancer has spread. Almost all cases of SCLC are related to smoking. It is extremely rare in a person who has never smoked.
What is the most aggressive type of lung cancer?
Small cell lung cancer is the most aggressive type of lung cancer. Although cancer cells are small, they grow and spread quickly to other parts of the body, such as the brain, liver, and bones. Because SCLC grows rapidly, it tends to respond well to chemotherapy and radiation therapy, although it recurs in most people.
Other types of lung cancer
Other types of tumors can appear in the lungs, including:
– Carcinomatous tumors of the lung
These tumors usually grow slowly. They represent less than 5% of lung tumors.
This type of cancer is most often found in the lining of the lung, but it can also develop in the lining of the abdomen, heart, or chest. It is linked to exposure to asbestos, a mineral
– Rare tumors
Other types of cancer that can appear in the lungs include adenoid cystic carcinoma, sarcoma, lymphoma, thymoma, and hamartoma (benign lung tumors).
Cancer that spreads to the lungs
Cancer that starts in another organ can metastasize to the lungs, although this is not considered lung cancer. For example, a tumor that starts in the liver but spreads to the lungs is still considered a liver tumor and should be treated accordingly.
– Bronchogenic carcinoma
In the past, the term “bronchogenic carcinoma” described lung cancers that originated in the bronchi: the large airways of the lungs. Today, this term generally refers to all types of lung cancer. In other words, “bronchogenic carcinoma” is just another way of saying “lung cancer.”