Lung adenocarcinoma is a type of lung cancer that develops in the cells responsible for making mucus. Forty percent of lung cancer cases are adenocarcinoma, making them the most common type. People ages 20 to 46 are more likely to develop adenocarcinoma, as are women.

People with lung adenocarcinoma tend to have a better prognosis (outlook) than those with other types of non-small cell lung cancer (NSCLC), such as squamous cell carcinoma or large cell carcinoma.

Symptoms of Lung Adenocarcinoma

Respiratory problems can develop if the lung tumors are pressing on organs in the chest or blocking airways. These can include:

• Chest pain that gets worse with coughing, laughing, or deep breathing
• Hoarseness
• Persistent cough, sometimes coughing up blood (hemoptysis)
• Shortness of breath/wheezing
• Changes in the color of mucus/phlegm (sputum)
• Increased sputum production

Although adenocarcinoma is cancer of the lungs, symptoms of the disease can be experienced in many parts of the body.

These may include:

• Dizziness
• Fatigue
• Loss of appetite
• Weakness
• Swollen lymph nodes
• Memory loss
• Bone fractures
• Unexplained weight loss
• Blood clots

It is also possible to develop whole-body syndromes known as paraneoplastic syndromes in cases of lung adenocarcinoma. These can include:

• Hypercalcemia — High calcium levels in the blood
• Horner’s syndrome — A problem with nerves in the face and eye
• Hypertrophic osteoarthropathy — A condition including arthritis and enlarged fingertips

How Is Lung Adenocarcinoma Diagnosed?

If your doctor suspects that you have lung cancer, they will run a series of imaging tests. These tests diagnose all types of lung cancer, including adenocarcinoma.

Imaging tests such as chest X-rays, CT scans, and MRIs can all give your doctor an inside look at your lungs. These techniques can create detailed pictures that can show tumors in the lungs and lymph nodes.

A biopsy may be taken using a long, hollow needle that is inserted into the lung to remove tissue. You may also undergo a bronchoscopy, which uses a thin, flexible tube with a camera attached to look down into the lungs for tumors.

What Causes Lung Adenocarcinoma?

Lung adenocarcinoma is primarily caused by smoking, but it is also common in nonsmokers. Other risk factors for developing this type of cancer include breathing in substances that irritate the lungs over long periods of time, such as:

• Air pollution
• Secondhand smoke, if you do not smoke
• Asbestos
• Radon
• Chemicals found in the workplace, such as radioactive ores and diesel exhaust

If an immediate family member has had lung adenocarcinoma, you are at a higher risk for developing it yourself. You are also at an increased risk if you have had radiation therapy to the chest to treat other types of cancer. This is also true for treating cases of breast cancer and Hodgkin disease.

How Does Lung Adenocarcinoma Differ From Other Types of Lung Cancer?

Adenocarcinoma differs from other types of lung cancer through the cells it affects and how it is targeted for treatment.

Adenocarcinoma develops in the glandular cells found in the lungs, which are responsible for making mucus. These cells are found in the air sacs (called alveoli), typically on the outer edges of the lungs. Adenocarcinoma also grows more slowly compared to other types of lung cancer.

Certain treatments that are used for lung adenocarcinoma are not effective in other types of lung cancer. For example, people with small cell lung cancer cannot be treated with the same targeted therapies because they usually have different genetic mutations than those found in adenocarcinoma.

Treatments for Lung Adenocarcinoma

Adenocarcinoma is the most common type of lung cancer, so there are several different treatment options:

• Chemotherapy
• Radiation therapy
• Surgery
• Targeted therapy
• Immunotherapy

In advanced cases of adenocarcinoma, palliative care can be given to make a person more comfortable by relieving symptoms of the disease.

Chemotherapy

Chemotherapy is a standard treatment in cancer care and can also be used to treat lung adenocarcinoma. Many times, chemotherapy is adjuvant therapy, meaning it is given in addition to other treatments to lower the risk of the cancer returning.

Common chemotherapy drugs used to treat adenocarcinoma include:

• Carboplatin
• Cisplatin
• Gemcitabine (Gemzar)
• Paclitaxel (Taxol)
• Docetaxel (Taxotere)
• Pemetrexed (Alimta)
• Vinorelbine (Navelbine)

Radiation Therapy

Radiation therapy (also known as radiotherapy) uses intense beams of radiation to shrink tumors. This can be done alone or in combination with other treatments, such as chemotherapy.

The two types of radiation therapy used to treat lung adenocarcinoma are brachytherapy (internal radiation therapy, placing radiation in or near the tumor) and external beam radiation therapy.

Surgery

Surgery is another treatment option used for adenocarcinoma. Depending on the size and position of the tumor, surgery may even be used to cure cancer. There are four main types of surgery used to treat lung cancer, including:

• Lobectomy — Removal of an entire lobe of the lung
• Pneumonectomy — Removal of an entire lung
• Sleeve resection — Removal of part of an airway, and the remaining ends are joined together
• Wedge resection (segmentectomy) — Removal of only one part of a lung lobe

Targeted Therapy

Targeted therapy for adenocarcinoma targets specific mutations that are common in people with NSCLC. Tyrosine kinase inhibitors are a type of medication most often used to treat advanced NSCLC (including metastatic cases). Your doctor will test for biomarkers in your tumor(s) to look for mutations that can be treated with these medications. A biomarker is a molecule found in blood, other body fluids, or tissues that is a sign of a normal or abnormal process, or of a condition or disease.

Mutations in the epidermal growth factor receptor (also referred to as EGFR) are treated with the following medications:

• Erlotinib (Tarceva)
• Gefitinib (Iressa)
• Afatinib (Gilotrif)
• Dacomitinib (Vizimpro)
• Osimertinib (Tagrisso)
• Amivantamab (Rybrevant)

Mutations in anaplastic lymphoma kinase are treated with the following medications:

• Ceritinib (Zykadia)
• Alectinib (Alecensa)
• Crizotinib (Xalkori)
• Brigatinib (Alunbrig)
• Lorlatinib (Lorbrena)

KRAS mutations (specifically the G12C mutation) can now be treated with sotorsasib (Lumakras), which was approved by the U.S. Food and Drug Administration on May 28, 2021.

Other, less common mutations can be treated by targeted therapies as well, including:

• BRAF mutations — Dabrafenib (Tafinlar)
• RET mutations — Pralsetinib (Gavreto) and selpercatinib (Retevmo)
• MET mutations — Tepotinib (Tepmetko) and capmatinib (Tabrecta)
• NRTK mutations — Entrectinib (Rozlytrek) and larotrectinib (Vitrakvi)

Immunotherapy

Immunotherapy uses antibody drugs to activate the immune system to recognize and kill cancer cells. These drugs are useful only in certain types of cancer, including adenocarcinoma.

One type of immunotherapy is PD-1/PD-L1 inhibitors. PD-1 and PD-L1 are immune checkpoints, which are used to turn the immune system on and off. Cancer cells have learned how to “hijack” these checkpoints and keep immune cells turned off so they cannot detect and kill the cancer. Checkpoint inhibitors have been developed to block this interaction, turning the immune system on to fight cancer.

Checkpoint inhibitors that target PD-1 include pembrolizumab (Keytruda), nivolumab (Opdivo), and cemiplimab (Libtayo). Atezolizumab (Tecentriq) is a checkpoint inhibitor that targets PD-L1. These drugs are used alone as first-line treatments or in combination with chemotherapy to help shrink tumors.

Another PD-L1 inhibitor, durvalumab (Imfinzi) is used to treat stage 3 adenocarcinoma when cancer cannot be removed with surgery, and the condition has not worsened after chemotherapy and radiation.

Ipilimumab (Yervoy) is another type of checkpoint inhibitor that works on the molecule CTLA-4, similar to PD-1/PD-L1. Yervoy is given either in combination with Opdivo with or without chemotherapy.

Palliative Care

In advanced cases of lung adenocarcinoma, palliative procedures can be done to help relieve symptoms associated with cancer. For example, a thoracentesis removes fluid from around the lungs. This procedure helps relieve shortness of breath.

Lung Adenocarcinoma Outlook

A person’s prognosis can be estimated using the five-year relative survival rates of others with similar cancer types. Lung adenocarcinoma is a type of NSCLC, and the American Cancer Society estimates the five-year relative survival rates based on data between 2010 and 2016:

• Localized cases — 63 percent
• Regional cases — 35 percent
• Distant cases — 7 percent
• All stages combined — 25 percent

These percentages are estimates and do not take into account the subtype of NSCLC (such as adenocarcinoma), age, and overall health.

As research continues to develop new detection methods and treatment options, these statistics may improve over time. New medications have been approved within the last year, and research continues to look for more.

Talk With Others Who Understand

MyLungCancerTeam is the social network for people with lung cancer. On MyLungCancerTeam, more than 6,000 members come together to ask questions, give advice, and share their stories with others who understand life with lung cancer.

Have you used targeted therapy to treat your lung cancer? Share your experience in the comments below, or start a conversation by posting on your Activities page.