Medically reviewed by Dr. C.H. Weaver M.D. Medical Editor updated 9/2020

Stage IIIA non-small cell lung cancer (NSCLC) consists of a single cancer mass that is not invading any adjacent organs, but has spread to nearby lymph nodes in the chest.

Stage IIIA cancers are subdivided into N1 and N2 subgroups. N1 cancers involve lymph nodes farther away from the heart and are easier to remove with surgery. N2 cancers involve lymph nodes that may be difficult to remove with surgery because they are located in the part of the chest cavity that is between the lungs and contains the heart.

Systemic adjuvant therapy improves survival for patients with stage IIIA NSCLC when compared to treatment with surgery alone and is now considered standard of care, and additional efforts are underway to evaluate new precision cancer medicines to further improve the outcome of individuals with early stage NSCLC. (1,2)

The following is a general overview of treatment for stage IIIA NSCLC. The information on this website is intended to help educate patients about their treatment options and to facilitate a mutual or shared decision-making process with their treating cancer physician.

Multi-modality Treatment

A combination of therapies has become the standard approach to treating patients with stage IIIA NSCLC. Individuals with stage IIIA NSCLC are typically treated with a local therapy to eliminate cancer cells in the chest and a systemic therapy that circulates throughout the body to kill cancer cells that may have spread to distant locations in the body. Local therapies include surgery and radiation and systemic therapy consists of precision cancer medicines, chemotherapy and/or immunotherapy. (3,4)


Role of surgery in the treatment of stage IIIA NSCLC: Since stage IIIA NSCLC has spread extensively to lymph nodes that are deep in the center of the chest cavity they are often difficult to remove with surgery. Administering systemic therapy and/or radiation therapy prior to surgery is one approach that doctors may use to shrink the cancer and increase the chance that it may be removed with surgery. However, patients are more susceptible to complications of surgery after systemic treatment. Therefore, the risks and benefits of surgery must be carefully weighed for each individual. (5)

Researchers have reported that select patients with stage IIIA NSCLC may benefit from surgery following chemoradiation. However, patients who are candidates for a pneumonectomy—which is surgery to remove an entire lung—have a higher risk of complications from surgery and the researchers suggest that they may benefit from foregoing radiation therapy before surgery.(6)

Thoracotomy: A thoracotomy is a surgical procedure to open the chest and remove cancerous lung tissue and is performed under general anesthesia. Surgical removal of the cancer may be accomplished by removing the entire lung (pneumonectomy), a lobe of the lung (lobectomy) or even a small segment of the lung (segmentectomy). In general, the less lung that is removed, the greater the preservation of lung function and the lower the risk of major side effects from the surgery. On the other hand, if too little lung is removed, there is an increased chance of a local cancer recurrence. Currently, most physicians recommend a lobectomy. A patient’s general overall condition, age and location of the cancer are other factors that may influence the type of surgery performed and the side effects associated with the surgery. Prior to surgery, patients should carefully discuss the risks and benefits of removing the cancer with their surgeon.

Video-Assisted Thorascopic Surgery (VATS): This is a form of minimally invasive surgery that utilizes a television camera. The advantages of the camera-aided procedures are that smaller incisions can be used and there is no need to cut through a rib, which is necessary for conventional thoracotomy. This results in quicker, less intrusive surgery, with a much smaller scar. However, using these new procedures requires significant skill and a great deal of training. There is less, or at least different, visibility with VATS. If a serious problem arises, VATS can be converted to an open or traditional procedure, creating a small additional risk.

Radiation Therapy

In 2020 the pivotal LungART clinical trial evaluating post-operative radiation therapy found no benefit when administered to surgically resected stage IIIA patients. (25)

Some patients with NSCLC however are not able to undergo surgery to remove their cancer. Advanced age and other medical conditions such as heart disease and diminished lung capacity make it more difficult for these patients to withstand surgery. For these patients, staging of their cancer may be relatively precise using newer scanning techniques, including positron emission tomography (PET) and they are often offered radiation therapy as treatment for their cancer. Studies have demonstrated that patients with stages IIIA NSCLC who are not able to, or do not wish to undergo surgery may be treated with radiation therapy alone. Results indicated that radiation therapy alone produced an average survival time of over 30 to 34 months, respectively.(7,8)

Chemotherapy and radiation therapy: Treating patients with both chemotherapy and radiation therapy is a standard treatment for patients with stage III NSCLC. However, the way in which these treatments are administered appears to make a difference. Researchers have reported that administering the two treatments together, or concurrently—a technique called chemo-radiation—appears to improve outcomes compared to administering the treatments sequentially, or one following the other. While chemo-radiation does appear to improve survival, this approach is also accompanied with increased side effects. (11,12)

Prophylactic brain radiation: Researchers have found that the most common site for cancer to spread in patients with stage IIIA NSCLC is the brain.(9) These patients may benefit from radiation treatment to the brain during their initial therapy, which is called prophylactic treatment. Results of a clinical trial indicate that prophylactic brain radiation reduced the rate of cancer recurrence in the brain from 30% to 8% and the overall chance of relapse in the brain from 54% to 13%. Researchers reported that patients who received prophylactic brain radiation did not experience impaired attention or visual memory after treatment.(10)

Systemic Therapy

Individuals with Stage IIIA NSCLC often already have small amounts of cancer that has spread outside the lung and cannot be detected with any of the currently available tests. Undetectable areas of cancer are referred to as micrometastases. The presence of micrometastases causes the cancer recurrences that follow treatment with surgery or radiation alone.

Systemic therapy is any treatment directed at destroying cancer cells throughout the body. An effective systemic treatment is needed to cleanse the body of micrometastases in order to improve a patient’s duration of survival and potential for cure.

Systemic therapies commonly used in the treatment of NSCLC

Chemotherapy: Treatment with chemotherapy after surgery is considered standard for stage IIIA NSCLC: A National Cancer Institute of Canada clinical trial showed that adjuvant chemotherapy increased the number of patients who lived 5 years or more from 54% to 69%, and US researchers have demonstrated that adjuvant chemotherapy increased the number of patients who survived 3 years or more from 69% to 82%.(13)

Neoadjuvant therapy: Neoadjuvant therapy is systemic therapy that is delivered before surgery with the goal of providing immediate treatment and reducing the size of the cancer for easier resection. A meta-analysis that included data from 15 eligible randomized controlled trials involving a total of 2,385 patients has revealed that neoadjuvant chemotherapy reduces the time to cancer recurrence and improves overall survival. Patients should discuss the potential risks and benefits of receiving chemotherapy prior to surgery with their treating physician. (14)

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Precision Cancer Medicines: Lung cancers may differ from one another based on what genes have mutations, and “genomic testing” can be performed on a blood sample or a biopsy sample of the cancer to identify specific cancer mutations driving the growth of the lung cancer. Once the cancer driving mutation is identified a specific precision cancer medicine or immunotherapy can be developed to attack that specific mutation or other cancer-related change in the DNA programming of the cancer cells.

  • EGFRm NSCLC: Approximately 10-15% of NSCLC patients in the US and Europe, and 30-40% of patients in Asia have epidermal growth factor receptor - mutated (EGFRm) NSCLC. These patients are particularly sensitive to treatment with precision cancer medicines known as EGFR-tyrosine kinase inhibitors (TKIs) which block the cell-signaling pathways that drive the growth of EGFR expressing lung cancer cells. Tagrisso (osimertinib) is a third-generation, irreversible EGFR-TKI designed to inhibit both EGFR-sensitizing and EGFR T790M-resistance mutations, with clinical activity against CNS metastases. In the Phase III ADAURA clinical trial Tagrisso adjuvant therapy administered to patients with stage IB, II and IIIA EGFRm NSCLC following complete cancer resection was determined to delay cancer progression.
  • Checkpoint Inhibitors are a novel precision cancer immunotherapy that helps to restore the body’s immune system in fighting cancer. They create their anti-cancer effects by blocking specific proteins used by cancer cells called PD-1 and PD-L1 to escape an attack by the immune system. Once PD-L1 is blocked, cells of the immune system are able to identify cancer cells as a threat, and initiate an attack to destroy the cancer. There are several PD-1 and PD-L1 inhibitors already approved for use in the treatment of more advanced NSCLC and they are being evaluated in earlier stage disease.(15,16) Imfinzi: The PD-1 checkpoint inhibitor Imfinzi precision immunotherapy when administered as sequential treatment following treatment with chemotherapy and radiation in patients with locally advanced, unresectable, stage III NSCLC delays the time to cancer progression and prolongs survival. Overall 50% of Imfinzi treated patients survived 4 years from treatment compared to 36% of those treated with chemoradiation without Imfinzi. The median survival duration was 47.5 months for Imfinzi versus 29.1 months for placebo.(24) Learn more... Keytruda The FDA approved the checkpoint inhibitor Keytruda (pembrolizumab) for first-line treatment for individuals not eligible to undergo surgical resection or definitive chemoradiation in April, 2019.

Treatment Follow-up

Patients with stage IIIA NSCLC are still at risk for developing a cancer recurrence, and others may still develop another lung cancer if lifestyle or other factors that increase their risk of developing cancer have not been changed. Researchers have been evaluating different screening methods and schedules for these patients in order to detect recurrent or second cancers early, when they are most treatable.

Researchers from the City of Hope National Medical Center recently determined that annual CT scans and chest x-rays three times per year may detect early second cancers in patients with previously treated early stage NSCLC who appeared to be cured.(8)

Strategies to Improve Non Small Cell Lung Cancer Treatment

Currently, there are several areas of active exploration aimed at improving the treatment of stage III NSCLC which are mainly available in clinical trials. Individuals should consider undergoing genomic biomarker testing to see if their cancer has a "targetable" cancer driving mutation that can be treated with a precision cancer medicine.

Precision Cancer Medicines: A targeted or precision therapy is one that is designed to treat only the cancer cells and minimize damage to normal, healthy cells. Precision cancer medicines that “target” cancer cells offer the advantage of reduced treatment-related side effects and improved outcomes and have become standard treatment for more advanced NSCLC. Therapies directed at mutations have improved outcomes in the treatment of advanced NSCLC and are now being evaluated in stage I-IIIA disease.

  • ALCHEMIST- the Adjuvant Lung Cancer Enrichment Marker Identification and Sequencing Trials – represents three integrated, precision medicine trials that are designed to identify people with early-stage lung cancer who have tumors that harbor EGFR and ALK gene alterations and evaluate whether drug treatments targeted against those molecular changes can lead to improved survival compared to current standard of care therapy alone.
  • Epidermal growth factor receptor (EGFR): Mutations in the EGFR gene may affect how NSCLC responds to certain drugs. EGFR contributes to the growth of several types of cancer, and drugs that block the activity of EGFR can slow cancer growth. (17) EGFR mutations are most common in people of Asian ethnicity, women, never-smokers, and those with a type of lung cancer known as adenocarcinoma. Researchers have reported that EFGR positive individuals treated with Tagrisso or Tarceva® plus chemotherapy have delayed time to cancer progression and improved survival compared to those treated with placebo or chemotherapy alone respectively.(17,18)
  • Anaplastic lymphoma kinase (ALK) gene: Up to 7% of NSCLC’s have an abnormal version of the ALK gene that contributes to the growth and of cancer. Lung cancers with this abnormality typically occur in non-smokers. The abnormal gene contributes to the growth and development of cancer cells. Medicines have been developed that target the ALK gene mutation and produced very promising rates of response in more advanced cancers.(19,20)
  • Glesatinib (MGCD265) is a tyrosine kinase inhibitor that is expected to target tumors with genetic alterations in MET or AXL genes. MET (mutations and gene amplification) and Axl (rearrangements) that occur in approximately 8% of patients with NSCLC. Genetic alterations in these targets have been implicated as drivers of tumor growth and disease progression in NSCLC.

Individuals without cancer driving mutations.

The combination of chemotherapy and immunotherapy improves overall survival for patients with advanced NSCLC. (1) Precision immunotherapy treatment of cancer has progressed considerably over the past few decades and has now become a standard treatment for advanced NSCLC. The immune system is a network of cells, tissues, and biologic substances that defend the body against viruses, bacteria, and cancer. The immune system recognizes cancer cells as foreign and can eliminate them or keep them in check up to a point. Cancer cells are very good at finding ways to avoid immune destruction, however, so the goal of immunotherapy is to help the immune system eliminate cancer cells by either activating the immune system directly or inhibiting the mechanisms of suppression of the cancer.

Researchers are mainly focused on two promising types of immunotherapy. One type creates a new, individualized treatment for each patient by removing some of the person’s immune cells, altering them genetically to kill cancer, and then infusing them back into the bloodstream the other uses precision immunotherapy medications to enhance the immune systems response to the cancer. Both are being evaluated in clinical trials. (21) Learn more…

Cryotherapy: Cryotherapy is a new treatment procedure that is still in investigative stages for various cancers. Cryotherapy is a technique that kills cancer cells by freezing them with sub-zero temperatures. During this procedure, hollow steel probes are placed inside and surrounding the cancer. Liquid nitrogen is then circulated through the probes, freezing the cancer cells and creating a ball of ice that surrounds the cancer. Once an adequate ice ball is formed, heated nitrogen is circulated through the probes. This process is then repeated.

Researchers from France conducted a clinical trial evaluating cryotherapy for the treatment of early stage lung cancer. Cryotherapy was performed through a rigid bronchoscope (a lighted tube that is placed into the bronchi). In this trial, 35 patients with early stage lung cancer received cryotherapy, 20% of whom had multiple locations of early stage lung cancer. One year following treatment, 91% of patients had a complete disappearance of cancer. Four years following treatment, only 10 patients experienced a local cancer recurrence. The treatment was well tolerated by these patients.(22)

Image-guided radiation therapy (IGRT): IGRT involves a CT scanner and computer modeling to accurately determine the size and depth of the cancer. In addition, this technique determines the measurement of the cancer through all stages of respiration and can direct the radiation more precisely while the patient is breathing normally. Researchers from Japan recently concluded that IGRT appears to be an effective and well tolerated radiation technique for patients with inoperable NSCLC with poor lung function. A distinct advantage of IGRT is that patients do not have to hold their breath during the treatment, which is necessary for standard radiation therapy. This is important because many patients with lung cancer have poor lung function and are not able to hold their breath during treatment.

Of the 21 patients with NSCLC involved in this clinical trial, 5 experienced a complete disappearance of detectable cancer, 11 patients experienced at least a 50% reduction in the volume of their cancer, and one patient had progressive disease following therapy. Approximately two years following therapy, only 5 patients had experienced a cancer recurrence. The treatment was well tolerated with no major side effects reported. Further clinical trials will are necessary to determine the role of IGRT in the clinical setting and demonstrate whether chemotherapy prior to or following radiation therapy may further improve long-term outcomes.(23)

Next:Surgery for Non Small Cell Lung Cancer

Next:Radiation Therapy for Non Small Cell Lung Cancer

Next:Precision Cancer Medicine for Non Small Cell Lung Cancer


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