Rare lung cancers

Rare lung cancers is a broad term used to describe types of lung cancer that are not very common, typically accounting for less than 5% of all lung cancers.

Examples of rare lung cancers, described according to their appearance under a microscope, include:

Adenosquamous carcinoma of the lung.
Large-cell neuroendocrine carcinoma.
Mesothelioma.
Pancoast tumors.
Salivary gland-type lung carcinoma.
Sarcomatoid carcinoma of the lung.

Because these cancers are uncommon, there is sometimes less research available, and they are often managed by specialist teams with experience in treating them.

Symptoms of rare lung cancers are usually similar to those of more common types of lung cancer. These may include a persistent cough, breathlessness, chest pain, unexplained weight loss, and tiredness. However, symptoms can vary depending on the type and where the cancer is in the lung.

Most rare lung cancers are diagnosed and treated in similar ways to non‑small cell lung cancer (NSCLC), so you may find it helpful to explore our non-small cell lung cancer resources. Some rare types share features with small cell lung cancer (SCLC).

If you are affected by a rare lung cancer, you may be referred to a specialist center for treatment and support. Treatment options depend on the exact type of cancer and how advanced it is, but may include surgery, chemotherapy, radiotherapy, targeted therapy, or immunotherapy, or a combination of these.

Adenosquamous carcinoma of the lung

Adenosquamous carcinoma of the lung is a rare type of lung cancer that is made up of a mix of the two main types of non-small cell lung cancer – adenocarcinoma and squamous cell carcinoma. It is diagnosed in the same way as other non-small cell lung cancers. Adenosquamous carcinoma accounts for around 0.4–4% of all lung cancers.

As adenosquamous carcinoma of the lung contains two different cell types, chemotherapy may differ from that used for other non-small cell lung cancers. Targeted therapies may be an option if specific genetic mutations are found.

Large cell neuroendocrine carcinoma

Large cell neuroendocrine carcinoma is a rare type of lung cancer that develops from specialized neuroendocrine cells in the lung. It is usually caused by smoking and is diagnosed using the same tests as other lung cancers. Large cell neuroendocrine carcinoma accounts for around 3% of all lung cancers.

Treatment depends on the disease stage. Early‑stage large cell neuroendocrine carcinoma is often treated in a similar way to non-small cell lung cancer, usually with surgery and chemotherapy. More advanced disease may be treated using approaches similar to small cell lung cancer, such as platinum‑based chemotherapy, sometimes with immunotherapy. You may find it helpful to explore our small cell lung cancer resources for more information.

Mesothelioma

Pleural mesothelioma is a type of cancer that develops in the tissue covering the lungs (the pleural membrane). It is often caused by exposure to asbestos.

The symptoms of mesothelioma are similar to other lung cancers. Diagnosis usually involves scans and tests on fluid or tissue from around the lung. Treatment depends on the stage at diagnosis but often includes combinations of chemotherapy, radiotherapy, and immunotherapy. The aim is usually to control the disease and manage symptoms.

Pancoast tumors

Pancoast tumors are tumors that develop at the very top of the lung. Most Pancoast tumors are non-small cell lung cancers, usually adenocarcinomas.

Because of where they grow, Pancoast tumors can press on a group of nerves called the brachial plexus, causing very specific symptoms, such as:

Pain in the shoulder or shoulder blade
Arm pain and hand weakness
A drooping eyelid, a smaller pupil, and flushing or reduced sweating on one side of the face (known as Horner syndrome).

Pancoast tumors can be difficult to diagnose because they do not always show up clearly on chest X‑rays, and their symptoms can be mistaken for other conditions. Treatment is similar to other non-small cell lung cancers, although surgery may be more complex because of the tumor’s position.

Salivary gland-type lung carcinoma

Salivary gland-type lung carcinoma is a very slow‑growing type of lung cancer that usually develops in the central airways. It was previously known as bronchial adenoma and includes two main subtypes: adenoid cystic carcinoma and mucoepidermoid carcinoma of the lung. Salivary gland‑type lung carcinomas make up around 0.1–0.2% of all lung cancers.

The symptoms of salivary gland-type lung carcinoma are similar to other lung cancers, and it is diagnosed using the same tests. The main treatment is surgery, although chemotherapy may be considered in some cases.

Sarcomatoid carcinoma of the lung

Sarcomatoid carcinoma of the lung is a rare type of lung cancer that is strongly linked to smoking and, in some cases, to asbestos exposure. It is a type of non-small cell lung cancer with tumor cells that can look like both carcinoma and sarcoma under the microscope. Around 0.3–3% of all NSCLCs are sarcomatoid carcinomas.

Sarcomatoid carcinoma is diagnosed using the same tests as other non-small cell lung cancers. It can be aggressive; treatment depends on how far the cancer has spread and may include surgery, chemotherapy and, in some cases, targeted therapies if specific proteins or genetic mutations are found.

If you have been diagnosed with a rare lung cancer, your healthcare team will support you with the tests, treatment options, and care that are most suitable for you.

Additional resources

References

European Lung Foundation. Rare lung cancers.
https://europeanlung.org/en/information-hub/lung-conditions/lung-cancer/rare-lung-cancers/.
Updated 2024. Accessed Apr 8, 2026.
Cancer Research UK. Mesothelioma cancer.
https://www.cancerresearchuk.org/about-cancer/mesothelioma.
Updated May 17, 2023. Accessed Apr 8, 2026.
Cancer Research UK. Pancoast tumours.
https://www.cancerresearchuk.org/about-cancer/lung-cancer/stages-types/types/pancoast-tumours.
Updated Jan 13, 2026. Accessed Apr 8, 2026.
Cleveland Clinic. Sarcomatoid carcinoma.
https://my.clevelandclinic.org/health/diseases/23937-sarcomatoid-carcinoma.
Updated Aug 8, 2022. Accessed Apr 8, 2026.