Which patients with relapsed/refractory NHL are appropriate for pre-CAR-T bridging radiation therapy?

Before answering this important question, I think that we, as Radiation Oncologists, should give serious consideration to moving past the terminology of "bridging radiation therapy" and instead refer to it as "pre-CAR-T infusion radiation therapy." Bridging therapy was initially an apt name; we were often radiating with the hope of holding disease at bay in order to keep the patient alive and medically stable while they awaited CAR-T infusion during the several-week process of CAR-T production. While that indication does still remain in some patients, there has been data from multiple institutions indicating that radiation delivered during this window may do more than just keep the patient alive until infusion; radiation may improve local c...

Bridging radiotherapy is appropriate/beneficial for patients who present with:

• Rapidly progressive disease that needs to be controlled during the CAR-T manufacturing period (3-6 weeks). Lymphoma at this stage is chemoresistant but radiosensitive. There are studies that show bridging radiotherapy to be superior to bridging systemic therapy (Yu et al., PMID 36309153; Pinnix et al., PMID 32589728), highlighting the importance of understanding the biology of the disease at this stage.
• High tumor burden and bulky disease. There are studies that show greater tumor volume/burden (MTV, LDH, tumor diameter ≥5cm, SUVmax ≥10) to be associated with higher risk of local relapse, and inferior survival (Vercellino et al., PMID 33180899; Dean et al., PMID ...