Stage 3A Non-Small Cell Lung Cancer

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Stage 3A non-small cell lung cancer (NSCLC) is considered a locally advanced cancer, meaning the tumor has not spread to distant regions of the body but it has spread to nearby lymph nodes. Roughly 10% of people diagnosed with NSCLC have stage 3A lung cancer at the time of diagnosis. Symptoms and prognosis can vary significantly in this stage.

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Understanding the various ways lung cancer can present at stage 3A and knowing all your treatment choices can help you and your oncologist plan a personalized approach to battling your disease. Newer treatments are making it possible for some patients to live longer, healthier lives.


An Overview of Staging For Non-Small Cell Lung Cancer


Marked by small tumors in the lungs and limited spread beyond the site of the primary tumor, stage 3A lung cancer is classified based on a diagnostic system from the American Joint Committee on Cancer (AJCC).

This is known as the TNM system and it includes three components:

  • Tumor (T): Size and location of the primary tumor 
  • Nodes (N): Whether cancer has spread to nearby lymph nodes
  • Metastasis (M): Whether or not lung cancer cells have spread to distant organs 

Numbers or letters are used with the T, N, and M notations to indicate how large or how advanced the cancer is for that area. There are four designations for stage 3A, which include the following:

Stage 3A Lung Cancer
T, N, M Designations Description
T1a/T1b/T1c, N2, M0 Size: No more than 3 centimeters (cm) Spread: To lymph nodes on the same side as the primary tumor Metastases: No spread to other body parts
T2a/T2b, N2, M0 Size: Between 3 cm and 5 cm and meets one or more of the following criteria: • Has grown into a main bronchus, but not within 2 cm of the point where the windpipe splits into the main bronchi • Has grown into the membranes surrounding the lungs • Partially clogs the airways  Spread: To lymph nodes on the same side as the primary tumor Metastases: No spread to other body parts
T3, N1, M0 Size: Meets one or more of the following criteria: • Is between 5 cm and 7 cm • Has grown into the chest wall, the inner lining of the chest wall, the phrenic nerve, or membranes of the sac surrounding the heart • Two or more separate tumor nodules are in the same lobe of a lung Spread: In the lymph nodes of the lung (on the same side as the primary cancer) and/or around the area where the bronchus enters the lung Metastases: No spread to other body parts
T4, N0/N1, M0 Size: Meets one or more of the following criteria: • Is larger than 7 cm  • Has grown into the space between the lungs, the heart, the large blood vessels near the heart, the windpipe, the esophagus, the diaphragm, the backbone, or the point where the windpipe splits to main bronchi • Two or more separate tumor nodules are in the same lobe of a lung Spread: May or may not have spread to lymph nodes on the same side as the cancer Metastases: No spread to other body parts


Because this lung cancer stage encompasses a range of tumor sizes and locations, symptoms of stage 3A lung cancer can vary. Some people have no symptoms with stage 3A lung cancer or assume that the early signs are related to seasonal illness. And some people experience symptoms of stage 3A lung cancer that prompt medical attention.

Common signs to watch for:

If left untreated, existing symptoms may progress or new symptoms can develop as the tumors grow and spread.


There is a range of treatment options, and the right treatment for you will depend on your TNM designation, your symptoms, and any other medical conditions that you have.

Working with your healthcare provider, you should review your treatment options as you determine which will offer you a chance to be cancer-free or improve the length of time you can manage the disease before it begins to progress.

Localized Treatment

Oncologists typically choose local treatments for stage 3A NSCLC. This involves therapies that work to eliminate the cancer where it is located (versus systemic therapy, in which treatment is sent throughout the body to destroy all cancer cells that have spread beyond the lungs).

Surgery and radiation are usually the preferred localized treatment options.

Sometimes neoadjuvant treatments and adjuvant treatments are used with localized procedures to improve the prognosis.

  • Neoadjuvant therapy: Usually consists of medication that can reduce the size of a tumor before localized treatments are used.
  • Adjuvant treatments: Medications given after surgery or radiation that work to destroy cancer cells that are undetectable on scans. Adjuvant medications are used to destroy these malignant cells to reduce the risk of recurrence.

Even with new breakthrough treatments, the survival rate for stage 3A NSCLC continues to be low. You may want to consider enrolling in a clinical trial. This is a type of research study where you would potentially receive treatments that are under development and not yet approved for treatment.


Combining chemotherapy and radiation—known as chemoradiation—is another approach to combating 3A NSCLC. Analyses of multiple studies show that treating the cancer with both forms of therapy at once provides a 10% reduction in the risk of death when compared with using just one of the therapies alone.

Targeted Therapy

Everyone with NSCLC is encouraged to undergo genetic testing (molecular profiling), which allows healthcare providers to see if your cancer cells have any of the genetic mutations that make the tumor responsive to certain therapies. These include EGFR mutations, KRAS G12C mutations, ALK rearrangements, and ROS1 rearrangements.

Targeted therapy drugs, such as Krazati (adagrasib), Tagrisso (osimertinib), Rybrevant (amivantamab-vmjw), or Lumakras (sotorasib), target cancer cells that have these mutations to keep them from spreading.


Immunotherapy is another option for some people. This treatment includes medications that boost the immune system and enable the body to fight cancer.

They do not work for everyone, but for some people with stage 3A NSCLC they may provide a way to reduce symptoms and the spread of cancer, and help to manage the disease long term.

For instance, the drug Infinzi (durvalumab) can be used following chemotherapy and radiation to improve progression-free survival for several years.


The overall five-year survival rate with stage 3A lung cancer is approximately 13%, but this varies widely depending on the designation of tumors, spread, and metastases.

Certain treatments are showing promise for improving the survival rate. Invasive surgery, for instance, is now more successful in this regard.

Your surgeon might perform a full lobectomy (removal of one of the five lobes that make up your lungs) or a pneumonectomy (complete removal of one lung) with good results for treating your tumor.

Radical surgical procedures for treating large tumors in stage 3A may provide a 50% increase in the five-year survival rate.

Of all the stages of lung cancer, stage 3A is the most variable and has the greatest number of options for treatment. That's why it is so important to be directly involved with the decision-making during your treatment.


A lung cancer diagnosis can be frightening and feel overwhelming. Support is important, so let your loved ones know how they can best help you on your cancer journey.

You can better cope with LCLC by learning as much as you can about the disease and asking questions. Consider joining a lung cancer support group, either through your treatment center or online, for support, practical tips, and to stay informed about clinical trials that might be appropriate for your particular situation.

Remember that you and your health care team are in control. No matter what others have experienced or recommend, you can chart your course by using the best available information, working in partnership with your oncologist and staying open to new possibilities.

5 Sources
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
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Additional Reading

By Lynne Eldridge, MD
 Lynne Eldrige, MD, is a lung cancer physician, patient advocate, and award-winning author of "Avoiding Cancer One Day at a Time."