The Study: The same approach used to cure lymphoma nearly a century ago has been rebranded for another, more creative undertaking. If stem cell grafts don’t take after a myeloablative allogeneic stem cell transplant, patients quickly find themselves up a creek without a paddle. Considering further myeloablative chemo would be more than most organs can handle, nodal radiation to achieve immunosuppression seems like a good place to turn when in desperate need of rapid re-conditioning for another transplant. Here is a German retrospective look at TNI as a reconditioning regimen for 33 pediatric patients with this exact problem over the past decade. TNI was pretty much what it sounds like with 7 Gy x 1 delivered to a mantle field above the diaphragm and inverted Y below while blocking critical organs. Remarkably, all patients achieved successful engraftment, with one patient requiring a third transplant. More remarkably, with the caveat of limited follow-up time for some patients, rate of event-free survival at 5 years was estimated to be 59%.
Bottom Line: Keep TNI in your back pocket for the unfortunate situation of a lethal stem cell graft failure after myeloablative chemo. | Wegener, Int J Radiat Oncol Biol Phys 2018