Lung cancer, also known as bronchogenic carcinoma, is the leading cause of cancer deaths in women and men both in the United States and throughout the world. Cancers that begin in the lungs are divided into two major types of lung cancer, non-small cell lung cancer (NSCLC) and small cell lung cancer (SCLC), depending on how the cells look under a microscope.

Each type of lung cancer grows and spreads in different ways and is treated differently.
lung cancer types


Non-Small Cell Lung Cancer (NSCLC) is the most common type of lung cancer, making up 80-85% of all cases.

Small Cell Lung Cancer (SCLC) makes up 15-20% of all lung cancer cases.





 Non-Small Cell Lung Cancer (NSCLC)

NSCLC typically grows and spreads more slowly than small cell lung cancer (SCLC). There are different kinds of NSCLC but the most commonly diagnosed are:
Adenocarcinoma – This is the most common type of primary lung cancer, that makes up just over 30% of lung cancer diagnoses. It begins in the cells that form the lining of the lungs, and has glandular properties.

Adenocarcinoma in situ (AIS) (formerly bronchioloalveolar carcinoma or BAC) – This is a rare subtype of adenocarcinoma that begins in the alveoli, and makes up about 3% of lung cancer diagnoses. It can spread without destroying other tissues.

Squamous cell carcinoma – This type of cancer begins in the thin, flat surface covering cells that line the passages of the respiratory tract, and makes up less than 30% of lung cancer diagnoses. This form of cancer is often due to smoking.

Large cell carcinoma – This type of cancer is poorly distinguished as it has none of the features that would allow it to be diagnosed as another type of NSCLC, and makes up about 9% of lung cancer diagnoses. It tends to grow quite quickly, and received its name due to the cells that look large and rounded under a microscope.

Large cell neuroendocrine tumors – This is the fast growing type of NSCLC and makes up about 2% of lung cancer diagnoses. Neuroendocrine cells contain little sacs called secretory granules that release substances such as hormones and peptides. Occasionally, however, neuroendocrine cells become overactive and, eventually, may become cancerous.

Undifferentiated carcinoma – These are undeveloped cancer cells that do not look like normal cells and multiply uncontrollably. These account for 10% of lung cancers.

Small Cell Lung Cancer (SCLC)

SCLC, also known as oat cell cancer, is a type cancer with cells that are smaller in size than most other cancer cells. It is less common than non-small cell lung cancer, but also responds well to chemotherapy and radiation therapy. It is a fast-growing cancer, usually caused by smoking, which typically begins in the large airways of the lungs, but is more likely to spread rapidly to other parts of the body, often the brain.

Causes of NSCLC and SCLC

Non-occupational causes of lung cancer include tobacco smoke and exposure to radon, an inert gas that develops from the decay of uranium. Occupational toxic exposure to hazards such as radiation, beryllium, asbestos, silica, diesel fumes and heavy metals may also cause lung cancer.


If you have been diagnosed with lung cancer due to toxic exposure, the dedicated attorneys at Madeksho Law Firm, PLLC can help.