Lung Cancer Screening Guidelines
Lung cancer is the leading cause of cancer deaths in the United States and the second most common malignancy in both men and women. Aline Zouk, MD, explains that many of these deaths are preventable via early low-dose CT scan screening among smokers and early-stage treatment. Because survival rates increase dramatically with earlier detection, the U.S. Preventive Services Task Force has updated its guidelines for screening—now, around 14 million Americans are recommended to receive yearly screenings. Dr. Zouk explains how the guidelines account for pack-years and age. The challenge for physicians, notes Zouk, is to encourage screening for patients before they exhibit any symptoms.
Featuring:
Aline Zouk, MD
Aline Zouk, MD is an Assistant Professor whose Specialties include Pulmonology.Learn more about Aline Zouk, MD
Release Date: June 2, 2022
Expiration Date: June 1, 2025
Disclosure Information:
Planners:
Ronan O’Beirne, EdD, MBA
Director, UAB Continuing Medical Education
Katelyn Hiden
Physician Marketing Manager, UAB Health System
The planners have no relevant financial relationships with ineligible companies to disclose.
Faculty:
Aline N. Zouk, MD
Assistant Professor, Pulmonology
Dr. Zouk has no relevant financial relationships with ineligible companies to disclose.
There is no commercial support for this activity
Release Date: June 2, 2022
Expiration Date: June 1, 2025
Disclosure Information:
Planners:
Ronan O’Beirne, EdD, MBA
Director, UAB Continuing Medical Education
Katelyn Hiden
Physician Marketing Manager, UAB Health System
The planners have no relevant financial relationships with ineligible companies to disclose.
Faculty:
Aline N. Zouk, MD
Assistant Professor, Pulmonology
Dr. Zouk has no relevant financial relationships with ineligible companies to disclose.
There is no commercial support for this activity
Transcription:
Melanie Cole (Host): Welcome to UAB Med Cast. I'm Melanie Cole. Joining me is Dr. Aline Zouk. She's a Pulmonologist and an Assistant Professor at UAB Medicine, and she's here to highlight the latest in lung cancer screening guidelines. Dr. Zouk, it's such a pleasure to have you here. As we get into this topic, and this is really a very big field now, and this is such an important preventive screening. What are you seeing as far as incidence and awareness of lung cancer? Are more people smoking or getting the message? Are more providers discussing smoking cessation with their patients? Address the prevalence of lung cancer, as well as to the benefits from screening.
Aline Zouk, MD (Guest): Thank you Melanie for having me. Those are really good questions that you are asking. And we'll start off a little bit by talking about the prevalence and the rates of lung cancer. We just had a report that came out in February of 2022 where lung cancer is now the second most common malignancy in both men and women. It is the third most frequently diagnosed in the United States and we're expecting about 230,000 cases in the year of 2022. So that puts it just behind breast and prostate cancer. It is also, by far the leading cause of cancer deaths in the United States with about 130,000 deaths per year. That's actually more deaths than the next four leading cancers combined. So for men, you have a one in 15 chance of developing lung cancer and for women, it's about a one in 17 chance. The good news that we're seeing is that new cases are decreasing probably, because of the decrease in rates of smoking and also the advances of early detection and treatment of lung cancer which is where the lung cancer screening plays a big role.
We know that survival rate depends on the stage at which the lung cancer is detected or how early the cancer is discovered with the survival rates being much higher in early localized lung cancer versus the disease with distant metastasis. So an early diagnosis or detection is extremely important in this case, especially with lung cancer.
So the recommendation is that we should be using the low dose CT scans. And this recommendation is a consequence of a big trial that was called the National Lung Cancer Screening trial. This trial had about 50,000 participants between the ages of 55 and 74 years old, who were either current or former smokers.
They needed to have a history of at least a 30 pack year history of smoking within the last 15 years. They were divided into two groups, the patients who had early low dose CT scans and patients who had yearly chest x-rays and this was done over three consecutive years. The results of these trials was that the group who was screened with a low dose CT scan had about a 20% decrease in lung cancer mortality. This was because they were able to detect lung cancer at its early stages. And there was also a 7% decrease in overall causes all causes of death. So this study for sure, showed that we should be using a low dose CT scan because it improves the rates of survival along among lung cancer. And this goes back to why is, why is it so important to detect early.
In the case of lung cancer, it makes a big difference to diagnose a lung cancer at early stages. So, the overall five-year survival for lung cancer is about 20%. But this varies dramatically between what based on the stage of diagnosis. So, for example, someone who has an early stage non-small cell lung cancer has a 63% five-year survival compared to a 35% five-year survival if you detect it at a later stage where there's regional involvement. This drops to about 7% if they are diagnosed at an advanced or metastatic stage. For small cell lung cancers, which is the other big type of lung cancer, the five-year survival rate for localized is lung cancer is 27% versus regional, it's 16% and only 3% when it's at a very advanced stage. So you can see here that definitely indeed early detection of lung cancer is very important for the prognosis, but unfortunately only 20% of our lung cancers are diagnosed at an early stage and about 50% are diagnosed at a later stage. And that's really where one of the rationales for lung cancer screening is coming from is can we shift that so that we're finding more cancers at an early stage to try to reduce that mortality, since we have effective treatments at an early stage.
Typically when, by the time we see our patients in clinic, they have come because they've already have symptoms and how that's, how their masses or their lung cancers are found. That's because it's already spread to where it's invading either an airway or it's had a pleural effusion, or it's now outside of the chest. And in those situations, that's where we are identifying patients at a very advanced stage. In other situations where we would identify malignancies earlier is when they are most often found because they've had a CT scan done for some totally other unrelated reason. And that's why screening has become so important is that it has the potential to help in so many patients that would otherwise we would be finding these cancers at a later stage. With screening, we can detect cancers at an earlier stage when they're still a small nodule. We're able to see that lesion or that nodule in the lung and detect it when it's still at a stage where we could have surgery and resect it.
Host: Dr. Zouk this is so interesting. So as you're telling us about the current screening guidelines as set up by the US Preventive Services Task Force. Give other providers, some practice considerations when they're discussing this with their patients. So speak a little bit about those screening guidelines and they've been updated. They're actually getting updated quite often now it's changed a few times. So speak to other providers with some practice considerations for that discussion and why the updated guidelines.
Dr. Zouk: Yes, of course. The recommendations have actually been updated, more recently in 2021. We want to remember that these recommendations is a consensus throughout many different networks and societies, including the National Comprehensive Cancer Network, the American Thoracic Society, the American Society for Clinical Oncology, American College of Chest Physicians and so forth, including the US Preventative Task Force. So the recommendations, that all these organizations, they recommend a yearly low dose CT scan for, to screen for lung cancer in patients that meet certain criteria. So this is not across the board. These are just recommendations for a specific group of high-risk patients.
The recommendations recently expanded in 2021, and now include patients between the age of 50 to 80 years old and patients who are current or former smokers with at least a 20 pack year history of smoking within the past 15 years. So a pack year smoking history is a multiplication of the amount of years that a patient has times the number of packs per day that the patient has smoked. These recommendations have expanded from the prior recommendations. So now we are screening patients as young, as 50 years old and patients who have pack year smoking history. So with these recommendations, the estimated population previously would reach about 8.1 million patients in the US versus now we are reaching about 14.5 million patients in the US and that makes a huge difference for screening.
Host: It does. And if we've gone up in eligible, people that are getting screened, do you have a theory or any sense of why maybe it hasn't even done better? What do you see as some research needs and challenges and about the benefits and data for people in underserved community where smoking and high mortality rates are higher?
Dr. Zouk: I think one of the biggest challenges that we face, is that although we now have these standardized recommendations, unfortunately on a national level, we only about five to 6% of the high-risk patients are actually being screened. And during COVID, in the last two or three years, these numbers are even significantly lower.
One of the reasons for the low number is not because of patient refusal, in fact, there's no real resistance when the patients are offered screenin. Even those who are reluctant to get radiation when they do hear that this is a low dose CT scan, they are much more accepting of it. I suspect that the majority of the low frequency of utilization for the screening is mostly based on the physician's part.
We're probably not ordering it or thinking about it as often as we should. Additionally, there is a lack of patient knowledge that to be asking for these tests, when they go to their primary care physicians.
Host: So interesting. So what happens if something's found on the low dose CT? What do the results show and who reads them? How can providers follow up on these screening findings once they've referred their patients for this screening?
Dr. Zouk: So the radiologists usually read the CT scans and give their recommendations based on how suspicious a lung nodule is. One of the, you bring up a good point because one of the things that we do in our clinic is that we discuss with our patients. We have a, what we call a shared decision-making process with our patients.
We know that while there is a lot of benefits towards lung cancer screening. we also have sometimes something called an indeterminate pulmonary nodule that is seen on the CT scan. These are just incidental findings that, that may represent other benign lesions or different abnormalities in the lung that are not necessarily lung cancer. So it could be anything from a benign pulmonary nodule to fibrosis or bronchiectasis or chronic infections, signs of inflammation, aspiration. Really, there's a broad differential diagnosis here, but, these are benign incidental findings.
And one of the things that we have to keep in mind, is that we have to talk to our patients before we embark on this journey of lung cancer screening to discuss with them that these things may happen. We may see these indeterminate, pulmonary nodules and really it actually happens around more than half percent of the time.
We want to make sure that the patient is aware of this because in certain scenarios, this may trigger other diagnostic testing or intervention such as a PET scan or a lung biopsy to make a final diagnosis. In in other cases we see very suspicious lung nodules that are much more concerning where we would discuss with them about getting a lung biopsy at that point.
Host: So then what would you like to let other providers know? Are the most important key messages or takeaways from this podcast on lung cancer screening and the updated guidelines? What would you like them to know as they're counseling their patients and trying to get patients more involved and even involved in smoking cessation programs? Give us the key takeaway.
Dr. Zouk: Yes. One of the, the biggest key takeaway here is that early lung cancer detection is key because we, it is, it has a concrete impact on patient survival, and we need to do everything we can to detect lung cancer at its early stages. Think about it and discuss with our patients early on. Because we do have strong evidence that a yearly low dose CT scanning is, in the appropriate group can detect lung cancer at an earlier stage and decreased mortality. So we know that we should be using this. Needless to say smoking cessation is also key in this equation because we know that smoking is the main risk factor for developing lung cancer.
And this is where I think prevention ties in with the screening is that we are also opening the doors to more of these discussions about smoking cessation. And then the last message to take home is the updated recommendations for the lung cancer screening guidelines.
Just to remind everyone is that it is for current or former smokers that are in between the age of 50 to 80 years old, who have had at least a 20 pack year smoking history and have smoked for at least the last 15 years.
At UAB, we do have a Pulmonary Nodule Clinic for those patients who have been diagnosed with a pulmonary nodule or lesion based on these yearly low dose CT scans. We have a multi-disciplinary thoracic team, that is composed of our radiologists, radiation oncologists, interventional pulmonologists, thoracic oncologists, and thoracic surgeons, where we work closely as a team to determine what the next best steps are for patients who have been discovered with a lung cancer. And whether that means a lung biopsy or surgery.
Host: Thank you so much, Dr. Zouk. Such a great podcast. Really informative. Thank you again. And a physician can refer a patient to UAB Medicine by calling the mist line at 1-800-UAB-MIST. Or you can always visit our website at UABmedicine.org/physician. That concludes this episode of UAB Med Cast. I'm Melanie Cole.
Melanie Cole (Host): Welcome to UAB Med Cast. I'm Melanie Cole. Joining me is Dr. Aline Zouk. She's a Pulmonologist and an Assistant Professor at UAB Medicine, and she's here to highlight the latest in lung cancer screening guidelines. Dr. Zouk, it's such a pleasure to have you here. As we get into this topic, and this is really a very big field now, and this is such an important preventive screening. What are you seeing as far as incidence and awareness of lung cancer? Are more people smoking or getting the message? Are more providers discussing smoking cessation with their patients? Address the prevalence of lung cancer, as well as to the benefits from screening.
Aline Zouk, MD (Guest): Thank you Melanie for having me. Those are really good questions that you are asking. And we'll start off a little bit by talking about the prevalence and the rates of lung cancer. We just had a report that came out in February of 2022 where lung cancer is now the second most common malignancy in both men and women. It is the third most frequently diagnosed in the United States and we're expecting about 230,000 cases in the year of 2022. So that puts it just behind breast and prostate cancer. It is also, by far the leading cause of cancer deaths in the United States with about 130,000 deaths per year. That's actually more deaths than the next four leading cancers combined. So for men, you have a one in 15 chance of developing lung cancer and for women, it's about a one in 17 chance. The good news that we're seeing is that new cases are decreasing probably, because of the decrease in rates of smoking and also the advances of early detection and treatment of lung cancer which is where the lung cancer screening plays a big role.
We know that survival rate depends on the stage at which the lung cancer is detected or how early the cancer is discovered with the survival rates being much higher in early localized lung cancer versus the disease with distant metastasis. So an early diagnosis or detection is extremely important in this case, especially with lung cancer.
So the recommendation is that we should be using the low dose CT scans. And this recommendation is a consequence of a big trial that was called the National Lung Cancer Screening trial. This trial had about 50,000 participants between the ages of 55 and 74 years old, who were either current or former smokers.
They needed to have a history of at least a 30 pack year history of smoking within the last 15 years. They were divided into two groups, the patients who had early low dose CT scans and patients who had yearly chest x-rays and this was done over three consecutive years. The results of these trials was that the group who was screened with a low dose CT scan had about a 20% decrease in lung cancer mortality. This was because they were able to detect lung cancer at its early stages. And there was also a 7% decrease in overall causes all causes of death. So this study for sure, showed that we should be using a low dose CT scan because it improves the rates of survival along among lung cancer. And this goes back to why is, why is it so important to detect early.
In the case of lung cancer, it makes a big difference to diagnose a lung cancer at early stages. So, the overall five-year survival for lung cancer is about 20%. But this varies dramatically between what based on the stage of diagnosis. So, for example, someone who has an early stage non-small cell lung cancer has a 63% five-year survival compared to a 35% five-year survival if you detect it at a later stage where there's regional involvement. This drops to about 7% if they are diagnosed at an advanced or metastatic stage. For small cell lung cancers, which is the other big type of lung cancer, the five-year survival rate for localized is lung cancer is 27% versus regional, it's 16% and only 3% when it's at a very advanced stage. So you can see here that definitely indeed early detection of lung cancer is very important for the prognosis, but unfortunately only 20% of our lung cancers are diagnosed at an early stage and about 50% are diagnosed at a later stage. And that's really where one of the rationales for lung cancer screening is coming from is can we shift that so that we're finding more cancers at an early stage to try to reduce that mortality, since we have effective treatments at an early stage.
Typically when, by the time we see our patients in clinic, they have come because they've already have symptoms and how that's, how their masses or their lung cancers are found. That's because it's already spread to where it's invading either an airway or it's had a pleural effusion, or it's now outside of the chest. And in those situations, that's where we are identifying patients at a very advanced stage. In other situations where we would identify malignancies earlier is when they are most often found because they've had a CT scan done for some totally other unrelated reason. And that's why screening has become so important is that it has the potential to help in so many patients that would otherwise we would be finding these cancers at a later stage. With screening, we can detect cancers at an earlier stage when they're still a small nodule. We're able to see that lesion or that nodule in the lung and detect it when it's still at a stage where we could have surgery and resect it.
Host: Dr. Zouk this is so interesting. So as you're telling us about the current screening guidelines as set up by the US Preventive Services Task Force. Give other providers, some practice considerations when they're discussing this with their patients. So speak a little bit about those screening guidelines and they've been updated. They're actually getting updated quite often now it's changed a few times. So speak to other providers with some practice considerations for that discussion and why the updated guidelines.
Dr. Zouk: Yes, of course. The recommendations have actually been updated, more recently in 2021. We want to remember that these recommendations is a consensus throughout many different networks and societies, including the National Comprehensive Cancer Network, the American Thoracic Society, the American Society for Clinical Oncology, American College of Chest Physicians and so forth, including the US Preventative Task Force. So the recommendations, that all these organizations, they recommend a yearly low dose CT scan for, to screen for lung cancer in patients that meet certain criteria. So this is not across the board. These are just recommendations for a specific group of high-risk patients.
The recommendations recently expanded in 2021, and now include patients between the age of 50 to 80 years old and patients who are current or former smokers with at least a 20 pack year history of smoking within the past 15 years. So a pack year smoking history is a multiplication of the amount of years that a patient has times the number of packs per day that the patient has smoked. These recommendations have expanded from the prior recommendations. So now we are screening patients as young, as 50 years old and patients who have pack year smoking history. So with these recommendations, the estimated population previously would reach about 8.1 million patients in the US versus now we are reaching about 14.5 million patients in the US and that makes a huge difference for screening.
Host: It does. And if we've gone up in eligible, people that are getting screened, do you have a theory or any sense of why maybe it hasn't even done better? What do you see as some research needs and challenges and about the benefits and data for people in underserved community where smoking and high mortality rates are higher?
Dr. Zouk: I think one of the biggest challenges that we face, is that although we now have these standardized recommendations, unfortunately on a national level, we only about five to 6% of the high-risk patients are actually being screened. And during COVID, in the last two or three years, these numbers are even significantly lower.
One of the reasons for the low number is not because of patient refusal, in fact, there's no real resistance when the patients are offered screenin. Even those who are reluctant to get radiation when they do hear that this is a low dose CT scan, they are much more accepting of it. I suspect that the majority of the low frequency of utilization for the screening is mostly based on the physician's part.
We're probably not ordering it or thinking about it as often as we should. Additionally, there is a lack of patient knowledge that to be asking for these tests, when they go to their primary care physicians.
Host: So interesting. So what happens if something's found on the low dose CT? What do the results show and who reads them? How can providers follow up on these screening findings once they've referred their patients for this screening?
Dr. Zouk: So the radiologists usually read the CT scans and give their recommendations based on how suspicious a lung nodule is. One of the, you bring up a good point because one of the things that we do in our clinic is that we discuss with our patients. We have a, what we call a shared decision-making process with our patients.
We know that while there is a lot of benefits towards lung cancer screening. we also have sometimes something called an indeterminate pulmonary nodule that is seen on the CT scan. These are just incidental findings that, that may represent other benign lesions or different abnormalities in the lung that are not necessarily lung cancer. So it could be anything from a benign pulmonary nodule to fibrosis or bronchiectasis or chronic infections, signs of inflammation, aspiration. Really, there's a broad differential diagnosis here, but, these are benign incidental findings.
And one of the things that we have to keep in mind, is that we have to talk to our patients before we embark on this journey of lung cancer screening to discuss with them that these things may happen. We may see these indeterminate, pulmonary nodules and really it actually happens around more than half percent of the time.
We want to make sure that the patient is aware of this because in certain scenarios, this may trigger other diagnostic testing or intervention such as a PET scan or a lung biopsy to make a final diagnosis. In in other cases we see very suspicious lung nodules that are much more concerning where we would discuss with them about getting a lung biopsy at that point.
Host: So then what would you like to let other providers know? Are the most important key messages or takeaways from this podcast on lung cancer screening and the updated guidelines? What would you like them to know as they're counseling their patients and trying to get patients more involved and even involved in smoking cessation programs? Give us the key takeaway.
Dr. Zouk: Yes. One of the, the biggest key takeaway here is that early lung cancer detection is key because we, it is, it has a concrete impact on patient survival, and we need to do everything we can to detect lung cancer at its early stages. Think about it and discuss with our patients early on. Because we do have strong evidence that a yearly low dose CT scanning is, in the appropriate group can detect lung cancer at an earlier stage and decreased mortality. So we know that we should be using this. Needless to say smoking cessation is also key in this equation because we know that smoking is the main risk factor for developing lung cancer.
And this is where I think prevention ties in with the screening is that we are also opening the doors to more of these discussions about smoking cessation. And then the last message to take home is the updated recommendations for the lung cancer screening guidelines.
Just to remind everyone is that it is for current or former smokers that are in between the age of 50 to 80 years old, who have had at least a 20 pack year smoking history and have smoked for at least the last 15 years.
At UAB, we do have a Pulmonary Nodule Clinic for those patients who have been diagnosed with a pulmonary nodule or lesion based on these yearly low dose CT scans. We have a multi-disciplinary thoracic team, that is composed of our radiologists, radiation oncologists, interventional pulmonologists, thoracic oncologists, and thoracic surgeons, where we work closely as a team to determine what the next best steps are for patients who have been discovered with a lung cancer. And whether that means a lung biopsy or surgery.
Host: Thank you so much, Dr. Zouk. Such a great podcast. Really informative. Thank you again. And a physician can refer a patient to UAB Medicine by calling the mist line at 1-800-UAB-MIST. Or you can always visit our website at UABmedicine.org/physician. That concludes this episode of UAB Med Cast. I'm Melanie Cole.