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 has spread to nearby lymph nodes. Roughly 10% of people have stage 3A lung cancer at the time of diagnosis. Symptoms and prognosis can vary significantly among those whose disease is 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 have been increasingly making it possible for 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 divided into specific designations based on a diagnostic system from the American Joint Committee on Cancer (AJCC). This is known as the TNM system because it uses the letters T, N, and M to identify specific characteristics of the cancer.

  • Tumor (T): Size and location of the primary tumor 
  • Nodes (N): Whether the 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)

SpreadTo lymph nodes on the same side as the primary tumor

M0 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 is not within 2 cm of the where the windpipe splits into the 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

M0 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

M0 metastases: No spread to other body parts

T4, N0/N1, M0

SizeMeets 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

M0 metastases: No spread to other body parts


Because this level of lung cancer 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.

These are the common signs of lung cancer to watch for:

If left untreated, these symptoms will progress as the tumors grow and spread.


The wide variation in types of tumors and lymph node involvement has lead to conflicting ideas about how to destroy the cells and manage the symptoms of stage 3A NSCLC.

Working with your doctor, you should review all the pros and cons of treatment options as you determine which will offer you a chance to be cancer-free or to at least improve the length of time you can manage the disease before it begins to progress.

Localized Treatment

Typically, oncologists choose to use 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 refer to medications given after surgery or radiation that work to destroy cancer cells that are present but undetectable on scans. Adjuvant medications destroy these malignant cells and, hopefully, prevent a 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 study that attempts to improve the survival rate for cancer by using not-yet-proven treatments.


Combining chemotherapy and radiation—known as chemoradiation—is another approach to combating 3A NSCLC that can be very effective. 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 doctors to see if your cancer cells have any of the genetic mutations doctors are now able to specifically treat. These include EGFR mutations, ALK rearrangements, and ROS1 rearrangements.

New targeted therapy drugs can work on the cells that have these mutations to keep them from spreading the cancer.


Immunotherapy is another exciting 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 provide a way to manage the disease long term without having the cancer spread or symptoms get in the way of living.

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 able to be more successful in this regard.

In the past, certain types of surgery were not encouraged for stage 3A cancer. Today, when faced with large tumors, surgeons are able to 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.

Radical surgical procedures for bulky 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.

Consider joining a support group to gain emotional support, but also because these groups can help you stay informed about clinical trials that might be appropriate for your particular situation.

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