Dr. Patricia Rivera & the UNC Lung Cancer Screening Clinic

Falk: Why should I get screened? There are these CT scanners in malls. It would almost imply that everybody should be screened. Presumably there’s a smaller group of individuals who really are at risk. Who are they?

Rivera: That’s correct. They are patients between the ages of 55 and 77, patients who smoke 30-pack-years or greater, and who have quit within the last 15 years

Falk: What’s a pack year?

Rivera: Twenty cigarettes a day, each day, for a year, is one pack year. So patients have to meet those criteria in order to be eligible for screening and in order for Medicare and insurance companies to pay for screening.

One pack a day for thirty years is a 30 pack year history. Two packs a day for 15 years is a 30 pack year history, etc. So we take a very detailed smoking history, and if they have quit, the guidelines state that you’ve quit within 15 years. For patients who’ve quit longer than that, the guidelines say you shouldn’t be screening those patients, because presumably the risk of lung cancer decreases, but I think we are still trying to best define the individuals who will most benefit from screening. I’m not sure that we are completely convinced that it’s only age, and smoking history, and pack years that have to be taken into account.

Through many different organizations-national and international organizations, we are working to define the criteria, if you will, and identify the patients who are most at risk for this disease, because things like gender, race, prior history of cancer, family history of cancer, the presence of COPD – these are really important additional risk factors that we have to take into consideration.

One of the things that we do in our screening clinic is we will get a referral: let’s say it’s a patient who quit smoking 17 years ago. Well, based on the guidelines, you’re not eligible for screening. But what if that patient has COPD, what if their mother died of lung cancer, what if they have a history of head and neck cancer? I use risk prediction models that have been developed and published extensively after the large screening trial was published, and I help patients identify what their true risk is. There’s a great deal of education that goes on in the clinic, and discussion, and true shared decision-making.

Falk: It implies though, that you as a patient have stopped smoking. Is there any reason to screen in somebody who’s still smoking?

Rivera: Yes, especially for those who are still smoking, but one of the very important components of screening is a smoking cessation program. That’s one of the things that we are most proud of in our program. We have a smoking cessation counselor in our screening clinic, and before patients come to our clinic, they’re contacted by our nurse practitioner, there’s a discussion that takes place in preparation for the visit about how much are you smoking, have you thought about quitting, these are the things we’re going to talk about. I think that goes hand in hand. In fact, we have a very nice paper that was just recently published from the large screening study that showed if you quit smoking, and were being screened, the mortality was reduced even further. The two are critical going hand in hand, smoking cessation and screening.

Falk: If I came to your clinic would I expect a CT scan on the first day I meet you?

Rivera: On the same day.

Falk: So I come in, I get educated, I get a risk assessment, and we get a CT scan.

Rivera: Right. And it’s read the same day by a chest radiologist who is part of the screening clinic. We have three dedicated chest radiologists, who then provide me with the result. I have the ability to look at the CT with the patient and then we make a plan for follow-up. Our goal is to be as comprehensive as possible to make it easy, and multidisciplinary, so patients are getting input from all providers.

Falk: In other words, during that visit I get to see my CT scan and go over it with you. In other words, there’s not a delay in “whoops I’ve had my CT scan, I wonder what it shows.”

Rivera: No, the only delay is if the patient doesn’t want to have it done that day, or if they’re having any symptoms that suggest a respiratory illness. I don’t like to get screening CTs if someone is sick. That’s really the only reason not to do the scan the same day.

Falk: Let’s talk about finding incidental shadows or images. You’re looking at a CT scan and there’s a confluence of shadows that is not clear to a chest radiologist. It’s not clearly a mass but it’s not normal. What happens then?

Rivera: It all depends on the appearance of the finding, and we are fortunate that we have fairly good guidelines that provide us with follow-up for what we call the “indeterminate nodules.” It’s a good point that you bring up because one of the problems with screening is that we find a lot of nodules. In fact, in the national lung cancer screening trial, 25 percent of patients had nodules, and 96 percent of those nodules were benign.

Falk: So there’s a finding on CT that look abnormal, it’s a round density, and 96 percent of them will not be cancer.

Rivera: The important thing to remember is that the majority of these nodules that are detected on screening are followed over time. We are very fortunate at UNC that we have a very good algorithm in place, if you will, and we follow the guidelines. We follow what’s called the “Lung-RADS” very similar to “Bi-RADS,” what radiologists use to read mammograms. Radiologists have devised guidelines for nodules detected on screening that give very good recommendations and that’s included in every report as to how you should follow those. It’s rare that we jump to a biopsy right away, unless of course it’s a very suspicious lesion and the likelihood of cancer is very high.

The goal of a well-designed screening program is to screen the high risk patients, with the goal of detecting cancer at an early stage, but being very careful not to subject patients to unnecessary procedures. I think that’s our mission, and I think we’re doing a pretty good job of carrying that out.

Falk: Getting a CT scan is not without some potential risk because of the low dose of radiation that one gets.

Rivera: It is low – it’s about 2 millisieverts of radiation, which is pretty low. The American Radiology Society has done a lot of work to ascertain the risk of exposing individuals to this kind of radiation. At the end of the day, for individuals who are at high risk for lung cancer, the benefit of screening for detection of lung cancer significantly outweighs the potential risk of radiation exposure. But you have to remember that low dose means just that – institutions need to be committed to doing these scans with 2 millisieverts radiation, which is a pretty low dose. That’s why when you mentioned earlier all these places doing CT scans – “Come get your CT scan” – if I were a patient I wouldn’t want that. I would want to go to a place that I knew had exactly what the guidelines recommend. These scans should be done with minimal radiation exposure, and should be interpreted by dedicated chest radiologists, so that unnecessary downstream procedures are not taking place.

Falk: One could imagine the adverse consequences to a patient who gets a CT scan that’s not read by a chest radiologist – it’s read by a competent general radiologist who finds a nodule who then makes the patient concerned enough, that they either have to get more of these CTs or perhaps, even an invasive procedure to get tissue, which may or may not be a necessary thing to happen.

Rivera: Absolutely. One of the most important concerns about lung cancer screening is just that. Can we reproduce the results from the national lung cancer screening trial? – which was done in centers that had a great deal of expertise, all CTs read by a dedicated chest radiologist, a lot of internal control, healthy patients, younger patients- on the younger scale of patients 55-77. Are those results generalizable? We don’t know the answer to that. The best that we can do is to try to replicate the infrastructure of the NLST with multidisciplinary teams that have expertise in lung cancer care, expertise in diagnostic procedures. If you have to have a diagnostic procedure you want someone with expertise in navigational bronchoscopy or endobronchial ultrasound or transthoracic needle – you want dedicated chest radiologists, interventional pulmonologists, thoracic surgeons—you really want a team of people who have expertise in the care of these patients, and who do this every day.

Falk: Let’s say I’m 55, I’m going to get a scan every year for 22 years? You’re saying once you start this, I’m going to get screened…

Rivera: Every year, until you reach the age where you no longer need to be screened – again, by Medicare guidelines 77, by the USPSTF, it’s 80. Or you’re 15 years out from smoking or you develop a medical condition that competes, an illness that is significant enough that it competes for dying from lung cancer.

Even within a cohort of 55-77, with 30 or greater pack-years of smoking and quit within 15 years, we know based on some really sophisticated studies that have been done, that some patients are very low-risk within that group and some are very high-risk. What we are trying to do is better define the cohort of patients and to come up with risk prediction models that will help us identify those that are really the ones that will likely benefit from screening. That’s where risk factors like COPD, family history, are important.

Falk: So I’m a patient and I’ve stopped smoking, I’m feeling fine. Why are some patients who are good candidates for screening not screened?

Rivera: I think it’s multifactorial. Probably one of the most important factors is access to health care. Or access to insurance. Patients who don’t have insurance have to pay out of pocket. There have been studies that have looked at people who are at most risk – the heavy smokers, older patients, and there’s a great deal of nihilism in smokers. I think it’s a problem with lung cancer – it’s “I brought this on. I inflicted this upon myself.” There’s nihilism in patients, in physicians, nurses, and the health care community. So it’s a disease that no one wants to talk about, no one wants to think about.

Falk: It strikes me if you went through the exercise of stopping smoking and you managed to do that, adding that extra step of wanting to be sure that if you developed a lung cancer and you picked it up early, that should be motivation enough.

Rivera: It should be, and it probably is for many patients. You have to remember that because you quit it doesn’t mean that your risk is down to zero. In our clinic, of all the patients that I have seen, only one has declined screening. Most patients—once they hear what this means and once they see the results, are very willing.

The other thing that I have found is very reassuring is that most patients have been very willing to talk to the smoking cessation counselor and be engaged in this commitment to quitting smoking.

Falk: What do you want physicians or other providers to know when they’re referring a patient to you?

Rivera: I’d like them to know that it is a comprehensive, multidisciplinary clinic that provides expertise in nodule follow-up, in radiology interpretation, that we have smoking cessation counselors available, and we have a really good system in place because we have developed a lung cancer screening registry. A research registry in collaboration with members of the Radiology department, Dr. Louise Henderson who is an epidemiologist who has been an instrumental part of the breast cancer registry. She and I, and members of the Pathology Department, and Thoracic Surgery have worked very hard to develop this registry. We have a system in place where we track results of CTs, we track nodules, we make sure patients come back for their follow-up, we communicate with the providers, we communicate with the patients.

Falk: Once you’re identified in this process, close tabs on you are appropriate.

Rivera: To make sure nothing falls through.

Falk: What’s more, long term, you’re going to learn a lot about a broader population and how they do, which should help refine guidelines going forward.

Rivera: Absolutely, that’s our goal.