BETA - What is a tandem transplant? When would you consider a tandem transplant?

What is a tandem transplant? When would you consider a tandem transplant? So a tandem transplant is an application of a stem cell transplant back to back within about three to six months of the first one. And the goal is to get people into a deep remission. So this was a relatively useful technique when we did not have such good induction treatments pre-transplant in multiple myeloma. So there were randomized clinical trials done in France which showed that compared to one transplant, a second transplant can benefit at least the patients who were not in a very good partial remission or a complete remission after the first one. So if you had a first transplant and you were not in a great VGPR or complete remission, you could go and have a second transplant to get you there. And those patients who converted did very well. So that was the basis on which tandem transplants were popular for a while. In the United States there were several centers that did tandem transplant. But then the BMTCT in the United States completed a large randomized trial which randomized patients in the new era, which is the era of good initial therapy, three-drug initial therapy, transplant and then maintenance. So with that standard, the tandem transplant did not add much or a second transplant did not add much to the first transplant. So patients who had a second transplant then land maintenance did the same as the patients who had one transplant then land maintenance. In the meanwhile, the European studies still continue to show a small but clear benefit for tandem transplant. So right now the jury is divided on this. For us the goalposts have moved, in my opinion, in the United States. For young patients who are transplant eligible, we actually need to get into a deep MRD-negative remission. If that is not possible with one transplant, I think you could consider a second transplant at that point as a tandem. On the other hand, if you get a deep, good induction response followed by a single transplant and you're already MRD-negative, which most people are going to be in the future, you wouldn't need a second transplant. So therefore my policy is to be a response adapted for the second transplant question. I hardly have to do it in less than 10% of my patients these days. So I keep the stem cells for a second transplant at relapse if needed, or hopefully never use it if the patient gets a really, really long remission. Where does tandem transplant therapy fit in with all the new therapies? So tandem transplant, believe it or not, became very popular in the 90s when we didn't have these new therapies. And so actually we had a study from France showing that if you didn't have the maximum response after one transplant, the complete remission, and then you did another one and you achieved the complete remission, two was better than one. But there were some studies that were negative. They didn't show that the second was advantageous. And there are new studies actually showing that for patients with high-risk disease, two may be better than one. But I think we don't do routinely. I personally don't do. I keep enough stem cells for two. I use a sandwich, the transplant, with this new targeted therapy before and after. Occasionally I do it in certain situations where I think the therapy before didn't work well. If I have a patient who struggled to achieve a response, who had a rapid progressive disease and the chemotherapy works, then yes, I said I'll give it a double dose. There is definitely a dose-relation response. There is randomized studies comparing 100 to 200 melphalan showing 200 better. So of course Barloghi is preaching there. He was preaching how his stem is not a little rock anymore. But the idea is to achieve the deepest response fast. If you have a rapidly proliferating myeloma, you don't want your myeloma lingering there and developing the resistance. You want to just blast it. You want to eliminate the clone. Sometimes a tandem transplant change in the conditioning can be reasonable. But because the studies were not all positive, it remains a controversial issue based on the situation, the patient, the genetic of the myeloma.