Radiation Therapy for Locally Advanced Non-Small Cell Lung Cancer, with Andreas Rimner, MD and John Robert Strawn, MD

May 5, 2015
Download MP3 (10.42 MB/11:23)

In this podcast, we will discuss new recommendations for radiation therapy to treat locally advanced non-small cell lung cancer, developed by the American Society for Radiation Oncology and endorsed by ASCO.

Transcript: 

ASCO: You're listening to a podcast from Cancer.Net. This cancer information website is produced by the American Society of Clinical Oncology, known as ASCO, the world's leading professional organization for doctors that care for people with cancer. In today's podcast, we will discuss new recommendations for radiation therapy to treat locally advanced non-small cell lung cancer, developed by the American Society for Radiation Oncology, and endorsed by ASCO. This podcast will be led by Dr. Andreas Rimner, who is a radiation oncologist at Memorial Sloan Kettering Cancer Center, and Dr. John Robert Strawn, a physician and patient advocate for non-small cell lung cancer. ASCO would like to thank Dr. Rimner and Dr. Strawn for discussing this topic.

Dr. Strawn: Hi, I'm Bob Strawn. I am a physician, but have worked as a patient advocate for a number of years on American Society of Clinical Oncology guideline committees for non-small cell lung cancer. I became a patient family advocate after my neighbor's smoking daughter died at age 41, with non-small cell lung cancer some 16 years ago. Today we are going to discuss the American Society of Clinical Oncology endorsement of the American Society of Radiation Oncology guidelines for the treatment of stage II and III or locally advanced non-small cell lung cancer. Dr. Andreas Rimner is with me today and will introduce himself.

Dr. Rimner: Hello, Dr. Strawn. I'm Dr. Rimner. I'm a radiation oncologist at Memorial Sloan Kettering Cancer Center, and I specialize in the treatment of thoracic malignancies, meaning cancers of the chest, and that is mostly lung cancer. So this falls into my area of expertise. And I was a member with you together on this Guideline Endorsement Committee.

Dr. Strawn: Thank you, Dr. Rimner, for being with us today. My first question for you, Dr. Rimner, is to briefly explain the primary recommendations in this guideline and who specifically does this guideline apply to.

Dr. Rimner: So these guidelines were, as you said, developed for patients with locally advanced non-small cell lung cancer. What that typically means is that there is a primary lung cancer that arose in one of the lungs and is limited to the chest. Meaning it has not spread beyond the chest, but it does involve typically the lymph nodes that are in the chest. These are the patients that we are talking about today. These patients are curable with our current treatment, and these treatments involve a combination of radiation therapy, chemotherapy, and/or surgery. The primary recommendations from these guidelines are that in patients that are not surgical candidates - meaning they are so called inoperable - chemotherapy and radiation, or a combination of the two, are the standard treatment of choice. These can be given at the same time, which is referred to as concurrently, one after the other, which is referred to as sequential treatment, or in some patients that are not chemotherapy candidates, radiation therapy can also be delivered by itself. At the same time, patients that are surgical candidates may have a surgical resection of their tumor in some combination with chemotherapy and/or radiation therapy, and there's different ways of combining them in terms of the sequence.

 

Dr. Strawn: What do these recommendations mean for patients?

Dr. Rimner: These recommendations really provide some orientation as to what the best evidence at this time is in terms of how they should be treated. I think the first question that we, as providers and patients need to be asked is, what is the so-called definitive therapy, meaning the therapy that has the ability to eradicate the tumor, and that is either surgery for patients that are candidates for surgery, or radiation therapy for patients who are not surgical candidates. And then this is combined with the other modalities, as needed.

Dr. Strawn: What are the risk and benefits of having radiation therapy at the same time as chemotherapy, versus having radiation therapy after chemotherapy?

Dr. Rimner: The benefits of radiation therapy at the same time as chemotherapy, is that we have found through multiple studies that that is the most effective way of treating locally advanced lung cancer in the absence of surgical resection. So when someone who is not a candidate for surgery, chemotherapy and radiation given together is the most effective way and gives the best chances of eradicating the tumor. However, that comes at a price, because the side effects are also higher with that combination, as opposed to giving radiation therapy after chemotherapy. And that has to be weighed carefully when we evaluate a patient. It has to do with the fitness of the patient, how old the patient is, the extent of the tumor, how large it is, where it is located, all those factors go into our evaluation. It has to do with what their breathing capacity is, whether they have lost a lot of weight, all of these factors, whether they have current infection. All these factors go into our decision-making to decide between giving chemotherapy at the same time as radiation therapy, or giving it one after the other. Ideally, we would like to give chemotherapy and radiation together at the same time to all patients, but that may be too toxic for some patients, so that has to be carefully weighed against the risks of this treatment.

Dr. Strawn: I have a comment and a question. An inherent problem with guidelines is there has to be a cutoff for literature review. The time between the cutoff and the publication of the guidelines can be significant. That time for the guidelines we are discussing today is about two years. In a rapidly developing medical field, patients will be faced with options not covered in these guidelines. I know you were investigating some of these options. My question is, what new techniques in radiation therapy are patients going to hear about, as they seek treatment today?

Dr. Rimner: You are absolutely correct with that comment. The guideline cutoff was two years ago. Actually, just this month a large study was published that was run by the RTOG, which is a cooperative group that runs national studies on radiation oncology questions. And it confirmed what is already in the guidelines - that the standard dose [vaccination?] for radiation is 60 gray. That is the recommended total dose of radiation to be given together with chemotherapy. So, even though the cutoff was two years ago, this study just came out and confirmed the guidelines as they are written right now. In terms of future developments, radiation oncology is a rapidly evolving field. The technology is really changing quite rapidly, and there are several studies that are ongoing right now in the field of thoracic radiation oncology, such as adapting the radiation fields to the tumor as it shrinks throughout therapy. So what we can do now is we can obtain scans, typically PET scans, also CAT scans, during the course of radiation therapy, and observe how the tumor shrinks, and then shrink our radiation field accordingly, in order to deliver a higher dose to the tumor and to also spare more of the normal surrounding organs, and thus minimize toxicities from the radiation treatment and the chemotherapy.

Other trials right now explore the role of proton therapy, that you may have heard about. Proton therapy is a different type of radiation that has some physical advantages over our standard photon radiation therapy that are, as of now, mostly theoretical, although there are some early pharmacy and clinical results. But there's a large national study ongoing to further explore the role of proton therapy, which might make a big difference in lung cancer patients. And then there are a lot of new targeted drugs that you may have heard about as well, and we are trying to figure out how we best combine them in locally advanced non-small cell lung cancer with the existing recommendations of chemotherapy and radiation. Those are just some examples of what is going on right now. And maybe the last study or last direction that people are thinking about in the field is how we can incorporate higher dose radiation therapy in a very specific and very precise way, and whether that would change or further improve our outcomes in locally advanced lung cancer.

Dr. Strawn: Thank you for your comments. As a final comment, I'd like to say that guidelines are not necessarily the final word, as Dr. Rimner has just discussed. New advances are continually being made. Patients should have frequent in-depth discussions with their oncology team to determine the treatment options that are the best for them. These discussions should include both benefits and potential side effects of any action. If the treatment plan is significantly different from published guidelines, ask for an explanation. The best treatment strategies for an individual patient should be developed by the patient's oncology team with shared decision-making with the patient.

Dr. Rimner: I completely agree with that comment. I think guidelines can provide a framework of what the best evidence is to date. But there are frequently situations where we have to make decisions on patients that do not perfectly fit a given guideline, or where there is something unusual or something slightly different where we have to discuss with the patient how to best approach it. And a multidisciplinary team really has a great benefit in that situation where a surgeon, a medical oncologist, and a radiation oncologist sit down together and develop an optimal treatment plan for a [given?] patient situation.

Dr. Strawn: I completely agree with that.

ASCO: Thank you Dr. Rimner and Dr. Strawn. For more information, visit www.cancer.net. And for more expert interviews and stories from people living with cancer, visit the Cancer.Net blog at www.cancer.net/blog. Cancer.Net is supported by the Conquer Cancer Foundation, which is working to create a world free from the fear of cancer by funding breakthrough research, sharing knowledge with physicians and patients worldwide, and supporting initiatives to ensure that all people have access to high-quality cancer care. Thank you for listening to this Cancer.Net podcast.