Lung Cancer / Mesothelioma
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Loading ...The topic of lung cancer screening is a very charged one, with most people, patients and physicians alike, having a strong opinion, either for or against. This is also an area in which there can be suspicion that any argument against screening is due to a financial calculation in which saving people from lung cancer isn’t worth the cost of imaging. Any screening discussion also entails a consideration of cost, financial and other, vs. benefit, but here I’ll focus on the issues related to the possible shortcomings of lung cancer screening in terms other than cost.
First, while CT screening can detect lung cancers, it also detects lots of little nodules that turn out to not be cancer. In fact, only a small proportion of nodules on CT are actually lung cancers, and nearly half of the patients involved in some screening trials have nodules identified. Those people who are told there is a nodule to follow now are subject to the anxiety of knowing they have a visible abnormality that is unlikely to be but possibly could be cancer. I have seen a few patients in my clinic who don’t have a cancer diagnosis but have a nodule that is being followed that appears unlikely to be cancer but which leaves them sleeping with one eye open all the time, worried about the possibility that they have lung cancer. There is also the risk that they will need to go through invasive procedures, ranging from a bronchoscopy or CT-guided biopsy to a video-assisted thoracoscopic surgery or even a full thoracotomy (open lung surgery) to get tissue and obtain a definitive diagnosis. In one series (abstract here), twenty percent of the thoracotomies were done for what turned out to be a benign cause. Of course, there are complications that may occur with an invasive procedure, such as a collapsed lung (pneumothorax), pain, risk of infection, and many other problems, even including death. Fortunately, that’s unlikely, but the mortality risk (i.e., risk of dying) from a lobectomy and mediastinal staging is in the 1-3% range, not zero. And it’s especially tragic if you’re chasing down a diagnosis that wasn’t actually cancer.
The other concern is that even detecting cancers may not actually translate to improving survival. To have screening be successful, you need to have a disease that is asymptomatic, can reliably be detected while there are no symptoms, and that can be effectively treated after early detection to improve the survival from the disease. But there are several potential biases that can lead us to think a screening test is more effective than it really is (figures below are all stolen borrowed from an older but very good New England Journal of Medicine review with reference here). For instance, there is lead time bias, which means that you find out something earlier but don’t actually change the outcome, and therefore the apparent survival after diagnosis is longer without better survival (the circle with the dot inside represents the screened person with a cancer):
(click to enlarge)
This would be like being told that a meteor is going to hit earth and destroy the planet on January 5, 2009. Not much help to know if we can’t change the outcome, but instead just learn the bad news sooner.
Another potential problem is length-time bias, which is that screening is most likely to pick up less aggressive cancers, because they have a longer interval of being visible on scans while remaining asymptomatic. The more aggressive cancers grow quickly enough that a yearly CT scan would have less opportunity to detect them before they cause symptoms:
The extreme version of this can cause something called overdiagnosis bias, which is when a cancer can be so slowly moving that it doesn’t really impact survival, but screening allows you to find these non-threatening cancers and show that survival is remarkably good, but in the control group these people would never have had symptoms, never have been diagnosed with cancer, and would have died of unrelated causes without ever knowing they had cancer:
If that concept seems familiar, it may be because you read a similar sentiment I recently described in a post about the potential of overtreating indolent bronchioloalveolar carcinomas. I wasn’t arguing against screening in that post. I was just saying that as someone who sees and treats a lot of BAC, I am seeing a significant fraction of these patients with a form of the disease that I’m concerned have such a slow moving cancer that it would never be a threat to their survival, and the treatment could be worse than the disease. That was me expressing my concern about overdiagnosis bias with BAC (although it can happen with other lung tumors, just less commonly), without using that terminology. And some publications have shown that screening studies have detected a significant number of tumors that have a remarkably slow doubling time (abstracts here and here), potentially taking years for a tumor of just a few millimeters to grow to 1.5 or 2 cm, and likely much, much longer to be a threat to survival.
One other issue is that even the advocates of screening aren’t suggesting that never-smokers or patients under 40 be screened routinely, but I know that there are many never-smokers with lung cancer who feel that screening would have been remarkably beneficial for them. But once you start expanding a screening program to a broad population at much lower risk, it both dramatically increases the cost of a screening program and raises the likelihood that what you find will be something other than what you’re looking for. So you end up spending way more money to cause far more anxiety, remove many more benign nodules with a risk for real complications, to find fewer and fewer real cancers. So even a CT screening process that the major proponents envision wouldn’t detect the vast majority of the 20,000-25,000 never-smokers in the US who are diagnosed with lung cancer each year (or the 30-50% never-smokers in most recent series from Asia).
I’ll conclude next time with some general comments of where we stand with screening in the US these days. But I’ll just clarify one point here, which is that while I have mentioned some areas in this discussion that may be shortcomings of screening, the arguments in favor of screening that I described in my last post also have some clear validity. I am not attacking motherhood and apple pie here. I am not arguing for or against a formalized lung cancer screening program here, just trying to offer everyone an idea of the ways in which people are considering this complex and very polarizing topic.
Posted in: Current Clinical Trials, Imaging and Response Measurement, Lung Cancer, Screening Issues and Controversy
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I’m disappointed in your views, doctor. These are the same weak arguments formerly used against breast, prostate and colon cancer screening. Surely, you can do better than that. Granted, no screening is perfect, but for those who are at risk AND choose to be screened, they should have the right to do so AND to have their insurance company cover it (as they would for the more politically correct cancers). OR these folks shoudl have the screening cost covered by the tobacco settlement funds that the government is using to fill potholes. But thank you for your concern with lung cancer patients. If someone didn’t know better, they might suspect the medical community was trying to make a profit from the hundreds of thousands of people affected or soon to be affected with this number one cancer killer.
dusty
Dusty,
I expressed several compelling arguments in favor of screening in my last post, which I would say are still very valid. I am not campaigning against screening here, but rather trying to provide a full discussion of a controversial topic. On this site I am working to provide comprehensive but understandable information, not proselytizing any viewpoint. I want this information to be balanced, whether it’s a consideration of one drug or another, or of one point and a counterpoint. I am specifically NOT talking about the financial issues here, saying that there are other factors to consider than costs. And I understand that some people believe that there is a conspiracy to provide a steady stream of patients with lung cancer who need expensive, profitable treatment. That is horrific, but it’s an argument that is not supported by the patients I see with a very indolent cancer who I suggest don’t necessarily need any therapy, at least not anytime soon. Oncologists make more money treating than not treating, so any concept that there may be clinically non-threatening cancers is against an oncologist’s financial interests.
One of the reasons I had dragged my feet on writing about screening is that it is so charged, and people tend to be so dismissive of the other side’s arguments (both sides are guilty of this). So if I try to present a balanced discussion of the reasons some people believe one way or another, I can guarantee that there will be people who will be antagonized and resent me for just considering the counterpoint to their view. My discussion of this issue is about ideas and data, not a personal attack against you or a campaign for or against screening.
For the record, there is room for me or others to believe that there is a component of bias in the screening studies but still feel that screening is likely to be beneficial.
I feel that the ideal is for someone to hear all sides of a debate and then come to their conclusions, rather than just to hear one side of an argument. Part of the problem with the lung cancer community, or many medical communities, is that patient and physician groups perceive each other as being on different “sides”. Neither group does well being isolated in an “echo chamber” of just hearing their own views and not understanding why other people don’t take their take on the topic as gospel.
I can see both sides of the screening issue, and I’d like to think that makes me sympathetic to all views, not an enemy to both sides.
-Dr. West
Your arguement on the downside of lung cancer screening has points that are well taken and it is nothing that I haven’t heard before. I’m just kind of glad that there wasn’t any other arguments against screening that I wasn’t aware of.
My decision will be to definately go into the I-ELCAP, I have not been deterred by the downside. I have had three breast biopsies due to mammography findings of suspicious nature, all three being very benign conditions. Sure, I’m anxious until the report comes back but there is relief too. And then if it was cancer hopefully I would have positive feelings that it was caught early.
One of the most important reasons for my soon to be participation in the I-ELCAP is that none of these issues are going to be resolved unless it is studied and the only way to do that is to step up to the plate and be a part of what could help.
I so much appreciate your candor in representing both sides. You helped me make the decision TO be screened inspite of the pitfalls.
Thanks, Dr. West!
Deb Clampitt
I can see where you tried to present both sides of the issue, Dr. West. However, surely you can understand the frustration of those of us you cannot quite grasp the “downside” of screening. You even begin you comments stating that screening for lung cancer is “VERY CHARGED”. So why is lc screening so much more charged than other types of early detection? Your comment about nodes that may not even be cancerous causing undue anxiety, but think of the anxiety from hearing a diagnosis out of the blue of advanced lung cancer and then sleeping with not ONE eye open both BOTH. Something being spotted in screening DOES NOT alway have to lead to invasive procedures (sounds like just a scare tactic to me) but what about watch and wait? Finally the argument that I have to put aside my bias and try to understand objectively and the one that blows my mind most is finding a cancer early hasn’t been shown to increase survival or change the outcome. Please explain that one again. Early detection in other cancers has certainly changed the outcome…hasn’t it. Unfortunely there is no preview button so I hope my post is understandable. My hat off to you for starting this discussion and I hope you will keep it going. Please don’t take anything personal. Out of frustraton and a sense of helplessness we sometimes shoot the messenger. Thanks Dr West. for having this forum.
jayc07
I understand both what you are saying and the sentiment behind it. I would say that screening of many types has been controversial and charged, but things evolve over time. I recall many fierce debates about screening mammograms among women in their 40s, as well as the value of mammograms in older women, as a rather current debate, and PSA screening is still a very charged issue. Yes, there is a certain element of “blame the victim” that may be a component in lung cancer screening, but controversy over screening is definitely not specific to lung cancer. It’s a gradual process, and perhaps in a few years there will be a broad consensus that lung cancer screening is appropriate for certain populations, and then we’ll fight over who comprises those populations.
Second, I don’t mean to imply to invasive procedures necessarily follow detection of a nodule. The I-ELCAP protocol and our general practice generally include regular follow-up of ambiguous nodules. Some people are fine with that, but others are very anxious with watching and waiting. And the clear majority of those nodules don’t turn out to be cancer.
The issue about survival benefit not being clear is that CT scans may be so sensitive that the cancers they are detecting are the ones that go a long time before causing symptoms, which means that they may also be a cancer that is not truly life-threatening. So you can detect more things that are technically called cancer, but people could potentially survive just as long if it had never been detected (I’m the MESSENGER here). The fact is that the I-ELCAP study found only 4% small cell lung cancers, so these are not exactly the same cancers we see in routine lung cancer practice, in which closer to 15% of lung cancers are the faster-growing SCLC.
We all have our own biases about things. It’s not reasonable to expect that someone diagnosed with lung cancer could or should view the discussion of screening from the same standpoint as someone who doesn’t. Part of my goal for this website is to bridge the gaps between viewpoints of patients and those of physicians and other health professionals. This is an area in which, taking a step back, I can see that it is very appropriate for anyone directly affected by lung cancer to feel very strongly about the issue. It is hard for all of us, myself definitely included, to see the world through other people’s eyes.
-Dr. West
What does money have to do with any of this? Is this the same agrument that we should not provide AIDS drugs to developing countries because it costs too much? Inserting money into a health discussion = concern for insurance company profits. We have a medical discussion VS a business discussion.
dadawg001
Screening generally includes a discussion of cost-effectiveness, but that tends to be a factor after the debate about survival benefit has been clarified better. Right now, people are largely debating whether early detection definitely saves lives. Considering the cost-effectiveness compared to other useful preventive programs would be the next step. Thus far, the discussion has been more focused on the medicine side than resource allocation. The concerns about screening and arguments against it being the standard of care have thus far been mostly from physicians who I don’t think have any clear financial stake either way.
Thanks for your reply. To clarify I have not been diagnosed with lc but certainly have been affected by it from the death of a family member. I do disagree with you because from what I read the medical community does have a clear financial stake. Think of the cost of screening(hundreds) vs. care later on (thousands). I also blame SOME in the medical community as well as the gov. and media for the blame the victim attitude. Truly, they have used lung cancer as the “poster child” for quitting smoking and that’s a shame. Sorry to be so blunt but that’s my opinion.
jayc07
Dr. West. Thank you for your reply. I want to commend you for being part of such a great website. Very up to date therapies and very thoughful discussion open discussion with a live knowledgable Physician.
Another arguement that you make on the side of not to screen, is that perhaps we are just catching cancer a bit earlier and that there may not be an overall survival advantage since we are just catching the cancer earlier. Well Dr. West, perhaps we should just scrap all cancer screenings and wait for patients to be symptomatic before we start looking for their cancers? If you do not subsribe to this theory, you must admit that there must be some advantage to detecting cancer early otherwise we wouldn’t have the screening processes in place. The only problem is that lung cancer requires an expensive CT scan test vs pap smears, PSA screens, mamograpy’s etc., which again bring us to cost.
If we pressure the insurance companies to pay for such costs annually, I am sure that the market will take care of the pricing for the CT exams. More centers will open that offer such exams (similar to all of the MRI facilities that you see now), and prices will have to become competitive. I have a center near me in Aurora, IL that offers spiral CT lung scanning for $150. Last time I checked, my insurance company was billed $105 for a chest Xray that I had in early 2006, so the costs are already becoming competitive.
I am sure that there is some bias involved with the testing in the ways that you have described, but if CT scan is a superior test for detecting lung cancer earlier over XRay, this is the real reason that we should perform CT lung cancer screening, not because there is a survival advantage or not. Perhaps detecting cancer earlier will open up a whole new area of research in prevention and stopping these very earliest detected cancers in its tracks, rather than where most of the research is currently being done with drugs on only the most advanced stages of lung cancer. Let use these screenings to be pro-active rather than re-active.
dadawg001
Folks,
Let me start by reiterating some things that people may be misinformed about:
1) I am not against LC screening.
2) I didn’t say I’m against LC screening.
3) I have never tortured a puppy.
What I am trying to do in this post about the challenges of LC screening is to have readers understand some reasons why not everyone thinks LC screening is the answer to everyone’s prayers.
To address the financial issues, there would be plenty of financial winners if LC screening were in place, like the radiologists who would have more CTs to do and charge for, and the surgeons who would have more cases to do that would otherwise have progressed beyond the point of being surgical candidates. I hope people here can consider me a sympathetic and dedicated part of the lung cancer community, and yet once I even utter an explanation for why some people aren’t convinced that screening is a miracle, I’m at risk for being tarred and feathered. But it seems there’s nothing I or anyone else can say to make some people believe that concerns about screening aren’t based primarily on a conspiracy to ensure that there’s plenty of advanced lung cancer to feed the coffers of drug companies and doctors.
And for me to explain the reasons why lung cancer screening can be problematic doesn’t mean that there is no value in screening for cancer at all. The purpose of screening is to detect a problem early, before it would otherwise be detectable, AND THAT LEADS TO BETTER OUTCOMES, but it wouldn’t be practiced if it just led to an earlier alert of the inevitable. I am NOT saying that lung cancer is unhelpful. But I do believe that SOME of the cancers that screening detects (prostate, lung, and other) is not necessarily clinically relevant disease. Leaving lung cancer for a moment, there are plenty of men who have prostate surgery that many people are concerned are being treated for non-threatening disease. THESE ISSUES ARE NOT JUST LUNG-CANCER SPECIFIC, and they are always controversial.
Screening shouldn’t be presumed to save lives just there is a program for screening — it was the other way around. We’re doing it in situations like colon cancer because colonoscopy was proven to save lives. Cervical cancer is remarkably reduced in the US because of Pap smears. The screening program followed the evidence. And right now the National Cancer Institute, American Cancer Society, and US Preventive Services Task Force all agree that breast, colon, cervical, and prostate cancer screening is benefical enough to recommend as a national policy, but NONE of those groups has recommended it for lung cancer.
I’m giving as full a coverage of a topic as I can, not just the views that everyone here wants to hear, but then get reamed for mentioning the other side. You might want me to say that there are guaranteed cures for everyone with lung cancer… I know some websites and health care practitioners who lead people to believe that. The easy thing would be to just tell you what you want to hear, but instead I’m offering a thorough version of the lung cancer world, which may include some negative reality creeping in.
And by the way, I posted on the topic of LC screening because so many people asked me to do it. It would be a lot easier to write just about all of the treatments everyone hopes will be a miracle.
-Dr. West
Dr. West,
I hope you do not become too gunshy after all the emotional responses you have gotten on this topic. You are to be commended for presenting both sides of what appears to be a very controversial issue. You are doing a great service to all your readers.
You do have to understand that a lung cancer diagnosis is devastating to the patient and their loved ones. In advanced disease there is so little hope to hold onto, and we are all grasping for some kind of direction that will give us all a chance of a longer, better quality life. It is sometimes hard to be objective when we are in that situation.
There is also the issue of who will pay for these screenings. I know of a few folks who are paying out of pocket to get screened for their own piece of mind. That is always an option for any of us, lacking support from the insurance community.
You have made many excellent points and please do not stop trying to inform and educate us, in spite of the sometimes heated backlash that you may get.
I was very relieved to hear that you have never tortured a puppy.
Tk
Tk
Yes Dr. West, these frustrations are not directed towards you personally. Presenting both sides serves to educate all of us more about the subject, and it certainly opens up the topic for discussion.
JIM
dadawg001
TK and Jim,
I do understand where you’re coming from. I get a bit defensive and frustrated because I, too, find it hard to see a situation outside my own perspective.
I’m glad the puppy comment can bring us to smile — there’s never enough humor on a cancer website.
And for the record, I had no comment about cats… 
I’ve just heard that they have developed a breath test of sorts that is like a billion times more sensitive than that of police breath alyzer tests. They think that they will be able to use this as an early detection for lung cancer as it will be able to detect the minute chemical changes in the breathe that are associated with lung cancer.
I’m not sure why they are wasting their time on this stuff, there has never been any evidence that detecting lung cancer early will improve overall survival. Seems like someone forgot to send these guys the memo.
dadawg001
I’ll try to find out more about this. The concept as been out there but hasn’t been nearly as well described and tested as imaging studies for screening.
Just thinking again today about the various biases mentioned in the previous discussions about against CT Scanning for at risk individuals.
One of the reasons against scanning was that there are likely biases built in to early screening and that early detection does not necessary prolong life (which I think is both incorrect and irrelevant.) But I was also reading some of the things that are favorable prognostic indicators including things like sex, race, age, performance status, etc. in some of these other studies/treatments for various cancers.
I got to thinking how can performance status be considered a favorable prognostic indicator in any type of cancer? Nobody with poor performance status is ever eligible for entry into clinical trials, and even the gold standard cancer treatments are not offered to people with poor performance status.
It seems to me that unless you include persons with poor performance status in these studies, you are building in a bias in your research, making your survival statistics even more puffy than the true effectiveness of the drug regimen.
Perhaps studies should be based on their effectiveness with the persons with the poorest performance status instead.
It would be a much more significant statistic to know that a treatment regimen produced 5 year survivals in the 40% range of patients with the poorest performance status, than if it produced 55-60% of the healthiest individuals that you can find and in the cancer’s earliest stages. Seems like researchers are puffing up (biasing) the effectiveness of their treatments and of their research statistics.
Jim
dadawg001
Jim,
It’s true that there is often a “selection bias” in research, in which the patients who are included on trials are not necessarily representative of the general population. I’m in the process of reviewing the small amount of research on treating elderly patients with post-operative chemotherapy. The studies typically include patients with a median age of around 59 or 60, and yet the median age of a new lung cancer patient is now closer to 70. So we really don’t have good info on what to do with real life patients from the younger, healthier patients who are more typically enrolled on trials.
One of the problems with poor performance status is that there are many unique ways that patients with a poor performance status are ill, so the study population ends up as a mish-mash of very different patients, which makes it harder to determine what your treatment is doing/can do. The other problem with patients who have a worse performance status is that some of them have major medical problems that could be as serious or more serious than lung cancer. If we need to learn what a treatment is doing for lung cancer, it becomes hard to interpret when several patients die of heart disease or emphysema or a different cancer instead.
That said, there have been a growing number of trials done for elderly and/or poor performance status in lung cancer, and elsewhere in cancer. There previously was next to no research, and now there are many more offerings, but they tend to be different trials than the ones for a healthier population. However, we’ve found that some of these trials can’t get a reasonable number of patients on them. They have trouble enrolling because the people most likely to go to a research center are the younger, fitter, more aggressive patients. Sicker patients tend to get treated closer to home, rather than make it to a major cancer center. In fact, people in oncology are often skeptical about the results that come from the most renowned cancer centers like MD Anderson and Memorial Sloan Kettering because many of the people who go there have come from vast distances and have already separated themselves from the people who don’t have the health or other resources to get on a plane and go to a huge cancer center. There is even data showing that one of the strong predictors of survival in cancer is the distance that someone lives from their oncologist’s office. It’s not that it’s better to travel a distance away to get chemo, but rather that the people who are going past 3 oncology offices to get to a bigger research center are doing it because they are fitter and more aggressive.
So I guess I’d summarize by saying that you’re right, the patients on trials don’t perfectly represent the real world, but we’re getting better all the time.
-Dr. West
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