There are several different types of lung cancer. The two main types of lung cancer are small cell lung cancer and non-small cell lung cancer (NSCLC).
Lung cancer is the
Keep reading to learn more about squamous NSCLC, including the causes, symptoms, treatment options, and outlook.
Researchers define lung cancer cells by how they grow, spread, and look under a microscope.
Squamous NSCLC occurs in the thin, flat cells that line the inside of the lungs. These squamous cells are present in the bronchi of the lungs.
People also call this type of cancer epidermoid carcinoma.
There are three main types of NSCLC.
The most common type is adenocarcinoma, which — according to one 2016 paper — accounts for about
According to the same 2016 paper, squamous cell carcinoma accounts for about 25–30% of all lung cancers. This type has a worse outlook than adenocarcinoma, with fewer treatment options available.
Large cell carcinoma accounts for about 5–10% of all lung cancers. It can start in any of several large types of cells in the lung. It grows and spreads
The other NSCLC cases are made up of rarer forms, such as:
- adenosquamous carcinoma
- sarcomatoid carcinoma
- salivary gland carcinoma
- carcinoid tumor
- unclassified carcinoma
The symptoms of lung cancer vary, depending on how advanced the condition is and whether it has spread to other parts of the body. There may be no symptoms during the early stages.
When symptoms do occur, the
- a persistent cough
- chest pain
- shortness of breath
- coughing up blood
- loss of appetite
- unexplained weight loss
- difficulty swallowing
People who have lung cancer may also experience frequent bouts of pneumonia or have enlarged lymph nodes.
Metastatic lung cancer refers to the spread of lung cancer to other areas of the body.
The cancer can spread by growing in nearby tissue, traveling through the lymph system, or traveling through the blood.
The lung cancer cells that travel to other organs remain lung cancer cells. They do not become cancer cells of the new organ. For instance, if lung cancer travels to the brain, it is metastatic lung cancer, not brain cancer.
Lung cancer that has spread to other parts of the body may cause other symptoms, including:
- bone pain
- nervous system changes, such as:
- swelling of the lymph nodes
A healthcare professional will determine the extent of lung involvement, the size of the tumor, and whether or not it has spread to the lymph nodes or other organs. This is known as staging.
Tissue samples taken during diagnosis can provide more specific information about the type of squamous NSCLC a person has. This information will guide treatment.
There are several types of standard treatment. It is
Healthcare professionals can use four types of surgery in lung cancer. These are:
- Wedge or segmental resections: They may use wedge resections or segmental resections to remove the tumor and the tissue around it.
- Lobectomy: Doctors perform lobectomy to remove a lobe of a lung.
- Pneumonectomy: This procedure involves removing the whole lung.
- Sleeve resection: This type of surgery involves removing part of the bronchus, which is the tube that leads from the windpipe to the lung.
This can be external or internal. Technicians will concentrate the radiation on the area of the cancer to kill cancer cells.
The types of medications a person receives depend on the type and stage of the cancer they have. Healthcare professionals may inject some of these drugs into a vein or directly into an organ or another specific area.
These drugs can attack specific cancer cells and may cause
These immune system proteins act by killing the cancer, blocking its growth, or keeping it from spreading. The types include vascular endothelial growth factors inhibitors, such as bevacizumab and ramucirumab, and epidermal growth factor receptor inhibitors, such as cetuximab and necitumumab.
Tyrosine kinase inhibitors
Tyrosine kinase inhibitors (TKIs) block signals within the cancer cell, preventing it from growing and dividing. Examples of TKIs include endothelial growth factor receptor TKIs and kinase inhibitors, which stop cancer cells with certain genes.
There are currently 17 TKIs with Food and Drug Administration (FDA) approval for treating NSCLC.
Mammalian target of rapamycin
These drugs prevent the growth of new blood vessels in cancer cells. An example of this type of drug is everolimus.
This therapy uses the body’s own immune system to kill cancer cells. Researchers developed these drugs to overcome cancer cells’ resistance to targeted therapies. They target the pathways the cells use to escape the immune system.
The currently available immunotherapy drugs are immune checkpoint inhibitors, including PD-1 inhibitor therapy, such as pembrolizumab and nivolumab, and PD-L1 inhibitor therapy, such as atezolizumab and durvalumab.
Other therapies and clinical trials
Some other therapies that a doctor may recommend for treating NSCLC include:
- laser therapy
- photodynamic therapy
Researchers are testing new drugs for lung cancer in
Specifically, trials are assessing the addition of radiosensitizers to the combination of radiation therapy and chemotherapy to see if it increases the ability to kill cancer cells.
Studies are also exploring vaccines against lung cancer.
The most significant risk factor for lung cancer is smoking cigarettes. Experts have linked this risk factor to approximately
Even occasional smoking increases the risk. However, the more a person smokes, the greater the risk. Quitting can lower the risk, but it will still be higher than in people who have never smoked.
Smoking also increases the risk of other cancers in almost any other area of the body.
The use of other tobacco products can also increase lung cancer risk, as can secondhand smoke.
Some other risk factors for lung cancer include:
- having exposure to radon, which is a natural gas that can get trapped in houses and buildings
- having exposure to workplace substances, such as:
- having a personal or family history of lung cancer
- having received radiation therapy to the chest during cancer treatment
- smoking and also taking beta-carotene supplements
- having exposure to air pollution
- having HIV
- being older
Doctors can order several tests and procedures to diagnose lung cancer and determine its stage. These include:
- History and physical: A healthcare professional will ask about the person’s health habits, job history, and previous illnesses and check their general body condition.
- Laboratory tests: Technicians take samples of blood, urine, and tissue.
- Chest X-ray: Doctors use this to look for masses on the lungs.
- CT scan: Dyes can make the organs more visible.
- Sputum samples: Technicians use these to check for cancer cells.
- Thoracentesis: This refers to the use of a needle to remove fluid from the space between the lung and the lining of the chest.
- Biopsy: Technicians take samples of tissue using a thin needle, using a bronchoscope, or carrying out a surgical procedure. Other technicians examine the tissue samples for gene mutations or specific antigens that can further help identify the type of cancer a person has.
- Other tests to help determine staging: These include:
The earlier a doctor diagnoses squamous NSCLC, the earlier treatment can begin. Treatments are available that can extend people’s lives, particularly if they receive their diagnosis in the early stages.
The treatment of cancer is a rapidly evolving field.
An exciting area of clinical research is personalized medicine. Researchers are designing trials tailored to the specific gene mutation that is causing the cancer.
Having regular checkups with a doctor is
Squamous NSCLC is one of the most prevalent cancers in the world. It is also a leading cause of cancer-related death.
There are numerous treatment options available for squamous NSCLC. The best choice depends on the stage of the condition.
Several trials are ongoing that focus on the specific mutations present in people with squamous NSCLC. The future of this approach, which is known as personalized medicine, is promising.