Non-Small Cell Lung Cancer – An Introduction

Last Updated: July 3, 2018

Thoracic oncologist Dr. Jyoti Patel explains the basics of non-small cell lung cancer (NSCLC), the most common type of lung cancer in the United States. In this patient education video, she discusses what NSCLC is, an explanation of staging and main treatment options, and information about advancements in research.

More Information

Cancer.Net Guide to Non-Small Cell Lung Cancer

What You Need to Know About Lung Cancer

The Stigma of Lung Cancer

Understanding Lung Cancer Screening

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Cancer.Net: Doctor-Approved Patient Information from ASCO®

What is Non-Small Cell Lung Cancer

Jyoti Patel, MD; Medical Oncologist; Member, American Society of Clinical Oncology: Non-small cell cancer is the most common kind of lung cancer. It will affect approximately 170,000 Americans this year. Essentially it is a cancer that forms in the lung, and we call it non-small cell, because that’s what it looks like under the microscope.

The reason that we lump all of non-small cell lung cancer together is the staging and prognosis is very similar and treatment is very similar. So people with early stage disease undergo surgery or radiation, patients with more distant disease may often have systemic chemotherapy, or immunotherapy, targeted therapy as their initial treatment.

Types of Non-Small Cell Lung Cancer

Dr. Patel: We subdivide non-small cell lung cancer into different types based on what the cells look like and where the cell of origin is. So, commonly we’ll talk about adenocarcinoma. Those come from the end of the respiratory tree from the alveoli that make our, that is where our oxygen and blood is interchanged. Squamous cell cancers are second most common and those come from the linings of the respiratory tree. And then a less common variant is large cell and neuroendocrine non-small cell. Those are our three major histologic types.

Staging of Non-Small Cell Lung Cancer

Dr. Patel: The first thing that you need to know that whatever stage it is, it’s very treatable. You think about what stage do I have, because that allocates the appropriate treatment.

If I am a candidate for chemotherapy, or immunotherapy, or targeted therapy, you want to understand which would be the best in your particular situation, and that often comes from pathologic testing.

And staging often includes some radiologic tests, like CT scans, MRI’s of the brain, or PET scans and that gives us the anatomy and sort of the extent of the disease. The next part of staging, of finding out more about your particular kind of lung cancer, is to understand either the histologic diagnosis, so that’s adenocarcinoma, squamous cell, or large cell neuroendocrine tumor, because that has relevance on additional biomarker testing and has relevance in what kind of chemotherapy would be given if it’s appropriate for your stage of disease.

The next piece, and the piece that’s so important to us now, is understanding if there is a genetic code that we can target in some cancers. So, particularly if there is a non-squamous tumor we recommend genetic testing to see if there are particular proteins or mutations, genetic mutations that we can target for more effective therapies.

Treatment Options by Stage

Dr. Patel: The treatment of non-small cell lung cancer depends primarily on the stage of disease. So if you have early stage, which we consider Stage I and II, often local therapy is the best initial treatment. So Stage I means that the tumor is confined to your lung. Stage II means that lymph nodes within the lung are involved. For those patients, an early referral to surgery is usually the best initial step.

Stage III disease is also often termed locally advanced, and that means that the cancer has generally spread to the lymph nodes in the center of your chest, sometime we call these mediastinal lymph nodes. These lymph nodes are close to the windpipe, and other essential blood vessels, and the heart, and often make resection with clear margin—so space around the tumor—really impossible.

And so what we tend to do is to do some sort of systemic therapy, that’s usually chemotherapy. And then we give local treatment, and that’s either radiation or surgery. This is a complex treatment plan, and it’s usually done with a team of doctors, like radiation oncologist, surgeons, and pulmonologists.

Patients who have Stage IV disease have cancer that spread to another organ, commonly that’s the bone, or the brain, liver, or adrenal glands, or it’s a tumor that has gone to the lining of the lung called the pleura, or to multiple sites in both lungs. Those patients are generally treated with systemic therapy.

Systemic Therapy Treatment Types

Dr. Patel: Most patients still get chemotherapy, the chemotherapy is much more tolerable than it ever has been. And it might be that treatment is once every three weeks, or every other week for some individuals. Targeted therapy is often a pill that’s given as a tablet every day at home and that is therapy that targets a particular protein that’s malfunctioning and causing the cancer to grow.

Immunotherapy has gained significant steam in the past year or two, and that’s because we’ve realized that in some people that have a high biomarker called PD-L1, that initial immunotherapy may be the first most appropriate treatment. Immunotherapy is generally an infusion given every once, once every 3 weeks or sometimes every 2 weeks, and that means it’s given by vein and it’s an antibody, a protein that blocks, this protein that’s upregulated, and by blocking it enables the immune system to function again to treat the cancer.

Advances in Treating Non-small Cell Lung Cancer

Dr. Patel: In non-small cell lung cancer, we’ve made significant strides, really in 2 categories, one is understanding how we can use immunotherapy to treat patients and to improve outcome. So some studies have shown that combining immunotherapy with chemotherapy looks very exciting and improves the time until the cancer grows again. Other studies have shown that up front treatment of patients with immunotherapy by itself may improve outcome.

We’re learning now that there may be a priming effect either with chemotherapy or with radiation to make immunotherapy more effective. So there are multiple trials that are ongoing understanding the best sequence of events. This is new territory for us, so the learning curve is rapid. When people ask me about survival expectations at 2 and 3 years, this is something that we’re just learning about, because now we’re finally seeing patients who are living beyond what any of our expectations were before.

The other big piece of cancer therapy and one that should not be overshadowed by the huge leaps we’ve made in immunotherapy, is really that we’ve, have a good understanding of many of the mutations that drive cancer, and this genomic profiling that’s usually done on tumor cells, sometimes is done in the blood, helps direct us to particular mutations that we can target.

We know that targeting therapy, targeting cancer with particular therapy is, is very effective. Often it means that we see fewer side effects because we’re just treating the cancer cells, and we know that we can see dramatic results with shrinkage and some, in some populations in 70 or 80 percent of patients who have these particular mutations.

The challenge is that these targeted therapies often work for some time. Some studies are showing several years of duration, but that often cancer gets smart and can find a way to outwit even the targeted therapy, and so now many research efforts are looking at, what do we do in the second, third, and fourth line setting in the patients who have had these oral therapies that have been so effective.

Where to Get More Information

Dr. Patel: If you’re diagnosed with non-small cell cancer, someone you care about is diagnosed with cancer, I’d suggest going to Cancer.Net, there’s a lot of information there about particular cancers, about strategies for staying healthy and living with cancer, as well as caregiving.

[Closing and Credits]

Cancer.Net: Doctor-Approved Patient Information from ASCO®

ASCO's patient education programs are supported by Conquer Cancer® The ASCO Foundation  

Special Thanks:

  • Dr. Mary Wilkinson, Dr. Raymund Cuevo, and the staff at Medical Oncology & Hematology Associates of Northern Virginia

  • Medical Oncology Hematology Consultants, Newark Delaware

  • Carolyn B. Hendricks, MD, Center for Breast Health

  • Dana-Farber Cancer Institute

  • Rockefeller Research Laboratories, Memorial Sloan Kettering Cancer Center

  • Palo Alto Medical Foundation, Sutter Health

  • The Adele R. Decof Comprehensive Cancer Center at The Miriam Hospital. The Miriam Hospital is a teaching hospital of The Warren Alpert Medical School of Brown University

  • University Hospitals Case Medical Center Seidman Cancer Center

  • University of Michigan Comprehensive Cancer Center

The opinions expressed in the video do not necessarily reflect the views of ASCO or the Conquer Cancer Foundation.

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