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 a few other, relatively rare types as well.
Some tumors contain cells that are both SCLC and a form of NSCLC.
Doctors must know the type of cancer you have to determine the best lung cancer treatment, as each one requires a different approach.
Non-Small Cell Lung Cancer
Non-small cell lung cancer (NSCLC) is the most common type of lung cancer, accounting for 80 to 85 percent of all cases.
There are different subtypes of NSCLC, arising from different kinds of lung cells, but the ones most commonly diagnosed are:
- Adenocarcinoma
- Squamous cell carcinoma
- Large cell carcinoma
Adenocarcinoma
Adenocarcinoma represents about 30 percent of all lung cancers.
Adenocarcinoma typically:
- Develops in cells in the outer part of the lung that would normally secrete substances such as mucus.
- Occurs mostly in smokers, but it is also the most common lung cancer to affect nonsmokers.
- Is more prevalent in women than men.
- Is the type you’re most likely to be diagnosed with if you’re young and diagnosed with lung cancer.
- Tends to be diagnosed earlier than other kinds of lung cancers.
There’s a rare subset of adenocarcinoma that begins in the alveoli (the tiny air sacs in the lungs), called adenocarcinoma in situ (AIS), previously known as bronchioloalveolar carcinoma.
AIS tumors account for about 3 percent of lung cancer diagnoses.
People with AIS tend to have a better prognosis (outlook) than those with other types of lung cancer.
Squamous Cell Carcinoma
About 30 percent of all lung cancers are squamous cell carcinomas.
This type of lung cancer starts in the thin, flat cells that line the passages of the respiratory tract, most commonly in the central part of the lung, near a main airway.
Squamous cell carcinomas are linked to smoking.
Large Cell Carcinoma
Large cell carcinoma makes up about 9 percent of all lung cancers.
This cancer can show up in any part of the lung. It usually grows and spreads rapidly, which makes treatment a challenge.
A type of large cell carcinoma, called large cell neuroendocrine carcinoma, is the fastest-growing NSCLC and has some of the same qualities as SCLC.
Other Subtypes of NSCLC
Other subtypes of NSCLC include adenosquamous carcinoma and sarcomatoid carcinoma. These are much less common forms of lung cancer.
Small Cell Lung Cancer
Small cell lung cancer (SCLC), sometimes called oat cell carcinoma, accounts for about 10 to 15 percent of lung cancers.
This cancer is a type of neuroendocrine tumor containing cells that are smaller than most other cancer cells.
SCLC is fast growing, with most people who have it receiving a diagnosis only after the cancer has spread.
Almost all cases of SCLC are related to smoking; it is extremely uncommon in people who have never smoked.
What Is the Most Aggressive Type of Lung Cancer?
Small cell lung cancer is the most aggressive kind of lung cancer.
Although the cancer cells are small, they grow and spread quickly to other parts of the body, such as the brain, liver, and bone.
SCLC tends to respond well to chemotherapy and radiation treatment, though for most people it will recur.
Other Types of Lung Cancer
Other types of tumors can occur in the lungs, including:
Lung Carcinoid Tumors These tumors typically grow slowly. They account for fewer than 5 percent of lung tumors.
Mesothelioma This type of cancer is most commonly found in the lining of the lung, although it can also start in the lining of the abdomen, heart, or chest. It is linked to exposure to the mineral asbestos.
Rare Tumors Other types of cancer that can occur in the lungs include adenoid cystic carcinoma, sarcoma, and lymphoma.
Bronchogenic Carcinoma
In the past, the term “bronchogenic carcinoma” described lung cancers that started in the bronchi — the large airways of the lungs.
Today, the term generally refers to all types of lung cancers. In other words, “bronchogenic carcinoma” is just another way of saying “lung cancer.”
The Takeaway
- Non-small cell lung cancer (NSCLC) and small cell lung cancer (SCLC) are the two main types of lung cancer.
- SCLC grows faster and tends to be more aggressive than NSCLC, and is often diagnosed after the cancer has spread.
- Your treatment plan will be tailored to your specific type and subtype of lung cancer.
Resources We Trust
- Mayo Clinic: Lung Cancer
- American Cancer Society: What Is Lung Cancer?
- National Cancer Institute: Find NCI-Supported Clinical Trials
- American Lung Association. Lung Cancer Screening Resources
- Centers for Disease Control and Prevention: Lung Cancer
EDITORIAL SOURCES
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