What to Know About Lung Adenocarcinoma

What is lung adenocarcinoma?

There are two predominant types of lung cancer:

• non-small cell lung cancer (NSCLC)
• small cell lung cancer (SCLC)

The ACS reports that NSCLC is much more common, making up 80% to 85% of all lung cancers.

Lung adenocarcinoma is a type of NSCLC, with the two others being squamous cell lung carcinoma and large cell carcinoma. About 40% of all lung cancers are NSCLC, according to the National Cancer Institute (NCI).

It begins in the glandular cells, which create and release fluids such as mucus and line the walls of your alveoli, the tiny air sacs in your lungs. When they turn cancerous, they begin to grow abnormally. They’re often found on the outer parts of the lungs.

Adenocarcinoma of the lung can be further divided into different subtypes based on factors like:

• the size of the tumor
• how the cancer cells look under a microscope
• whether the cancer has started to invade surrounding tissues

What are the symptoms?

Early on, a person with NSCLC may not experience symptoms. Once symptoms appear, they usually include a cough that does not go away. NSCLC can also cause chest pain when taking a deep breath, coughing, or laughing.

Other symptoms include:

• shortness of breath
• fatigue
• wheezing
• coughing up blood
• phlegm that’s brownish or reddish in color
• persistent cough
• hoarseness
• chest pain
• unintentional weight loss
• reduced appetite

The outlook for people with lung cancer is better when the cancer is found and treated early. If you develop any of the symptoms above, make an appointment with a doctor. They can perform tests to help find what’s causing your symptoms.

Growth and stages

NSCLC tends to form in the cells along the outer part of the lungs. In the precancerous stage, cells undergo genetic changes that cause the abnormal cells to grow faster.

Further genetic alterations may lead to changes that help the cancer cells grow and form a mass or tumor. Cells that make up a lung cancer tumor can break off and spread to other parts of the body.

The growth of lung adenocarcinoma happens in the following stages:

• Stage 0: The cancer has not spread beyond the inner lining of the lungs.
• Stage 1: The cancer is still early stage and has not spread to the lymph system.
• Stage 2: The cancer has spread to some lymph nodes near the lungs.
• Stage 3: The cancer has spread to other lymph nodes or tissue.
• Stage 4: The lung cancer has spread to other organs.

How serious is adenocarcinoma of the lung?

Depending on the stage of diagnosis, lung adenocarcinoma can be a serious illness. The more the cancer has spread, the more ongoing treatment you will need.

That said, a variety of factors can affect your outlook with adenocarcinoma of the lung. These include:

• the stage of your cancer
• the subtype of adenocarcinoma of the lung that you have
• how well your lungs are functioning
• whether certain genetic changes are present in the cancer cells
• your age and overall health

Who’s at risk?

Having a family history of lung cancer raises your chance of developing it yourself. Certain genetic mutations can also predispose you to it.

Other risk factors include:

• Smoking: People who smoke have a higher risk of developing lung cancer, according to the Centers for Disease Control and Prevention (CDC). Tobacco smoke contains thousands of different chemicals, and at least 70 of them are known to cause cancer. However, nonsmokers can also develop this cancer.
• Pollution and chemicals: Breathing highly polluted air can also raise your chance of developing lung cancer. This especially includes the gas radon. Breathing in chemicals found in diesel exhaust, coal products, and other hazardous materials like asbestos, uranium, arsenic, cadmium, and chromium increases your risk.
• Sex: Research indicates that females may be more at risk than males for this type of lung disease.
• Age: Younger people with lung cancer are more likely to have non-small cell adenocarcinoma than other forms of lung cancer, according to research discussed in a 2022 study.

How is the cancer diagnosed?

To diagnose lung adenocarcinoma of the lung, your doctor will first request your medical history. They’ll ask about the symptoms you’re having if you currently or have previously smoked and if you have a family history of lung cancer.

They’ll then perform a physical examination. At this time, they’ll get your vital signs and will listen to your lungs as you breathe.

The tests that may be ordered to help diagnose adenocarcinoma of the lung are:

• Blood tests: This can be a complete blood count or a blood chemistry test.
• Imaging tests: These may be a chest X-ray, a computed tomography (CT) scan, or a positron emission tomography (PET) scan.
• Bronchoscopy: During a bronchoscopy, your doctor will use a thin, flexible tube with a camera on the end to look inside your airways for signs of cancer. Your doctor may also request that tissue samples be collected.
• Sputum cytology: A doctor will view a mucus sample under a microscope to look for cancer cells. This test may not be as helpful for adenocarcinoma of the lung since this cancer is often on the outer edges of the lungs.
• Thoracentesis: If fluid is present in the space between your chest wall and lungs, your doctor will use a needle to remove a fluid sample. It can be reviewed under a microscope to look for cancer cells.

A lung biopsy is the only way to definitively diagnose adenocarcinoma of the lung. If the tests above raise suspicions of lung cancer, your doctor will request that a biopsy be collected from the affected area and examined under a microscope to look for signs of cancer.

This tissue can also be tested for proteins or genetic changes associated with adenocarcinoma of the lung. If present, they can affect outlook and may also be targets for treatments like targeted therapy and immunotherapy.

How is the cancer treated?

An effective treatment for non-small cell adenocarcinoma depends on the cancer’s stage. It may include:

• Chemotherapy: This may be done before surgery to shrink a tumor (neoadjuvant therapy) or after surgery to help kill any remaining cancer cells (adjuvant therapy)
• Radiation: This may be needed when surgery is not an option due to the extent of the cancer. It can also be used as a neoadjuvant or adjuvant therapy.
• Targeted therapy: These drugs home in on specific markers associated with cancer cells.
• Immunotherapy: These drugs help your immune system respond to cancer cells, usually in more advanced adenocarcinoma of the lung.

Surgery to remove all or only part of the lung is often required if the cancer has not spread. Other treatments are more likely to be needed if the cancer has spread.

Is lung adenocarcinoma cancer curable?

While it’s not impossible to cure lung adenocarcinoma, this is often difficult because the condition is commonly diagnosed at an advanced stage.

What is the survival rate for lung adenocarcinoma?

Overall, the 5-year survival rate for NSCLC depends on whether the cancer has spread:

That said, research suggests that people with lung adenocarcinoma may have a slightly higher 5-year survival rate compared to those with other types of lung cancer (32.3% vs 25.4%).

People with two subtypes of adenocarcinoma of the lung, adenocarcinoma in situ and minimally invasive adenocarcinoma have a better outcome, especially when the cancer is treated early with surgery. If surgery completely removes the cancer, the 5-year survival rate approaches 100%.

That said, survival rates are calculated based on data from many people with NSCLC and do not account for individual factors or recent advances in diagnosis and treatment. Overall, it’s best to discuss your individual outlook with your care team.

Takeaway

A lung adenocarcinoma is a form of NSCLC originating in the glandular cells of the lungs. Depending on its stage, this can be potentially life threatening. There are treatment options available that may lead to better outcomes.

Doctors and researchers also continue to develop newer, more effective treatments for adenocarcinoma of the lung. These can include new targeted therapy or immunotherapy drugs or new ways to use existing treatments.

Before being used on a larger scale, these new treatments need to be tested in clinical trials. If you’re interested in taking part in a clinical trial, talk with your care team. They can help you to find one that you would be a good candidate for.

You can also consider looking at clinical trials supported by the NCI. The LUNGevity Foundation also provides a clinical trial matching service via the phone or an online search tool.

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