DR FRIEDBERG: This addresses, I think, a very important clinical scenario that every oncologist probably deals with every week. And it’s fascinating to me how this has evolved from patients really demanding imaging as frequently as possible for the reassurance that it gives, that they’re in remission after treatment, to now patients really voicing concern over radiation risk. And certainly, several large data sets do suggest that imaging frequently does increase the chance of secondary cancers.
So this was a group of investigators that included investigators from Nebraska that just put together a series of patients with Hodgkin lymphoma and asked the question. It turns out about two thirds of the patients had scheduled surveillance imaging at the discretion of their physician. And the other third just had clinical surveillance only.
Now, that’s the major caveat in this study, because perhaps if a physician is worried about a patient, they would choose routine surveillance imaging or, if a patient refuses — this wasn’t a matched study in any way. But the bottom line was that there was no survival advantage to the routine surveillance imaging. And I guess put another way, whether a patient walks in or a problem is detected on physical exam versus finding a spot on a CAT scan, the salvageability of the Hodgkin lymphoma appeared in this series to be the same.
And I would say there are a few — it doesn’t surprise me that that’s the case. And I think this is another piece of evolving data that the use of routine surveillance imaging after treatment needs to be minimized, I think, particularly in Hodgkin lymphoma. This study did include — about half of the patients were early-stage patients. That’s a group where we know, a priori, that more than 90% of those patients are cured.
So you have to do a lot of scans to find a problem. And if you’re taking a patient like that and doing PET scans or CT scans every 3 months, like I see sometimes in the community, I think it’s very clear to me that those patients are being overimaged.
However, as we’ve discussed, either with PET imaging response or some of the technology and biomarkers, we know there are a group of patients with Hodgkin lymphoma that have a relatively poor outcome. And for that small group, it may make sense to do routine surveillance imaging.
So part of the decision of routine surveillance imaging in my mind is, what is the real chance that that patient is going to recur? Rather than just as a blanket, say, “We’re going to do it every 3 months for 2 years, and then every 6 months,” or whatever. And so it should be somewhat individualized.
But although the studies are very challenging to do, this study is consistent with the concept that you’re not hurting a patient by doing less frequent imaging. And, in fact, there are old studies done 20 years ago or 25 years ago now at Dana-Farber that suggested in the vast majority of cases even when surveillance imaging is done, it’s the patient who knows that there’s something happening. They’ll walk in and say, “I feel a new node,” or, “I’m feeling ill.” It’s not often the surveillance imaging that detects the progression.
DR LOVE: So Julie, you were an author on this paper. I’m curious what your thoughts were about the data and, also, what your clinical practice is in terms of surveillance imaging right now.
DR VOSE: So we had a clinical practice at our site not to do surveillance imaging on anybody, any type of lymphoma, for probably 15 to 20 years, actually. So we were the control in this particular analysis. And as you can see from this data, for people that have a very low risk of relapse, it really doesn’t benefit them. And we also did, as part of that, an economic analysis. And it was, I think, $600,000 or something for each relapse that was detected. So it was a huge amount of money. So I think economically speaking, with the cost of healthcare, that that’s another issue.
We just had this big discussion at NCCN guidelines yesterday, who to be able to recommend surveillance imaging for. And kind of what we came down to was, just as Jonathan was discussing, that perhaps there is a subset of high-risk, high-relapse potential patients that we should do it for. The question is, which patient population is that? And so that’s the question that has yet to be answered. But as a practice, we don’t do it at our site, only if the patient has symptoms, they come in with a problem or their lab or exam suggests that we should do a scan.
DR LOVE: Just final comment from Chris about this issue, any thoughts about it, and also, how it plays out in practice as you talk to patients. Are they comfortable with this?
DR FLOWERS: Yes. That’s a great point, too. So Julie and Jim and I have talked about this issue in the distant past. And I think they have fairly similar conversations with their patients in Nebraska, that we have in Atlanta, although at the end of those conversations, they choose not to do scans, in the vast majority of their patients, if not all. And at the end of discussions with my patients in Atlanta, they ultimately elect that they want to do scans based on the exact same data.
So I think this is a challenging discussion to have with patients. The things that we see from this study and from the diffuse large B-cell study that we’ll talk about later is that there now are even — at least more recent, if not more compelling evidence, that these scans are doing limited or no benefit, or at least very little benefit in terms of detecting relapses.
I think the concerns here, both for Hodgkin lymphoma patients and for diffuse large B-cell that we’ll talk about later, is that early on in therapy, there is an instance of relapse, at least in the first 2 years, that you’re concerned about and that you want to do something about, both from the patient’s perspective and from the oncologist’s perspective. What we see is that routine surveillance imaging is not it. That’s not the thing that’s going to help us to detect more relapses in these patients. Because these relapses are coming, but they’re coming in between the times when we’re doing scans. And we need to find some sort of risk-adapted strategy or some other strategy to detect these relapses and detect them in a way where we can do something about it that actually changes the impact of care.
DR EVENS: So Chris, how often off of a study — let’s say after the discussion — are you doing scans? What type of scans, and for how long?
DR FLOWERS: So we typically — that’s the discussion, is, “It typically occurs about every 6 months,” when we’re doing scans in the aggressive lymphomas, less commonly.
DR EVENS: Just CT scans, not PET scans. Right?
DR FLOWERS: Just CT scans. I think there really are no data to support the use of PET scanning as a surveillance imaging modality.
DR VOSE: We can see that in the community.
DR EVENS: I think that’s an important point. So just in general, they see it a lot. And there’s so many false-positives that you end up chasing your tail for. But yes, you can argue any scans, but if you are to scan, it really at a bare minimum should be a CT scan, at most, frequency every 6 months. I don't know how long you go for. We’ll go for 2 years from original diagnosis and then stop.
DR FLOWERS: Yes. I think beyond 2 years, it becomes more challenging to know what the benefits are, because that’s the highest risk of relapse at least for the aggressive lymphomas.