Shared insight on how best to assess a patient’s response to therapy for transplant-ineligible multiple myeloma.
C. Ola Landgren, MD, PhD:I’d like to go to the next slide. Polling question No. 3 is based on the response criteria that are used in clinical trials. Which of the following do you consider an adequate or successful treatment response in your patients? That is, a response that you feel that wouldn’t require a change in therapy. Is it MRD [minimal residual disease] negativity, complete response, VGPR [very good partial response], or other? Please vote. What’s a good response? All these options. Even if it’s VGPR, it depends on how we think about it. With VGPR or better, we like to see a CR [complete response] or MRD. We could interpret it in different ways. In the regular practice, how is response assessed? In your daily regular practice outside a consult trial, Craig, how would you do that?
Craig Hofmeister, MD, MPH: For standard patients, following along with their serum monoclonal protein light chains is usually the easiest for oligosecretory and nonsecretory. They’ll depend more on imaging. For the truly nonsecretory, we’re doing bone marrow biopsies if they have nothing else to follow and myeloma bone disease. That’s my standard in most patients.
C. Ola Landgren, MD, PhD:Would you do blood work only, or would you always do a bone marrow biopsy after trying combination therapy? We always repeat imaging. How would you deal with that?
Craig Hofmeister, MD, MPH: In general, no. In oligosecretory and nonsecretory, I’m doing lots of tests. That’s a small fraction of business. In 90% to 95% of patients, I’m just doing blood work. I don’t repeat imaging, and I don’t repeat marrow, because I rarely need to make treatment choices on that or a so-called nonsecretory escape change in the myeloma bone disease, which could occur but doesn’t happen often.
C. Ola Landgren, MD, PhD:Peter and Cristina, would you do imaging and biopsies?
Peter Voorhees, MD: For the patient with extramedullary disease who has extensive uptake on initial staging PET [positron emission tomography]/CT, particularly if they have high-risk disease futures genetically, I’d like to repeat PET/CT imaging after the initial therapy prior to transitioning to a maintenance platform to determine that all sites of the disease have responded as I think they have serologically. I want to make sure no subclones have advanced, in spite of treatment that might be. As far as repeat bone marrows, we do do that routinely after patients go through induction transplant and recover from transplant. I’m less inclined to do that in the transplant-ineligible patient population unless they’re in a clinical trial or unless they have oligo or nonsecretory disease, or if there’s something that doesn’t fit clinically. The patient has more severe cytopenias than I want to know about, but we’re not routinely repeating the transplant ineligible.
C. Ola Landgren, MD, PhD: Would you do the same, Cristina? Or do it differently?
Cristina Gasparetto, MD: I’d do the same, very similar to Peter. Patients with PET positive disease are a different category, and going from PET positive to PET negative is extremely important, so I do that. Like Peter, for nontransplant eligible, if I don’t make any changes in therapy, I probably won’t do the bone marrow but will just monitor the blood markers.
C. Ola Landgren, MD, PhD:In my practice, we also do similar to what you said, Peter, Craig, and Cristina. I probably would do little more biopsies. I’d like to repeat biopsies if I intend to give more effective therapy. As a prognostic indicator, the data tell me that some genetics are less powerful than achieving a deep response. In my practice, because we have set up all the tests, I’m testing in house so I can see how deep of a response I have. If patients are older and more frail, if the protein in their blood isn’t necessary or the patient doesn’t want to do it, I wouldn’t push as much as I would for a patient who’s a transplant candidate.
Transcript edited for clarity.