KEY POINTS
- This single-institution retrospective study included 21 patients with relapsed or refractory aggressive B-cell lymphomas treated with polatuzumab vedotin and concurrent radiotherapy, defined as polatuzumab vedotin within 3 weeks before or during radiotherapy.
- Most patients had diffuse large B-cell lymphoma (18/21, 86%), stage IV disease at diagnosis (57%), a median of 4 prior systemic therapy lines, prior CAR-T-cell therapy in 38%, and prior radiotherapy in 52%.
- Median radiotherapy dose was 25 Gy in 10 fractions; 19/21 patients received additional concurrent systemic therapy, most commonly rituximab or bendamustine plus rituximab.
- Acute grade 3 or higher hematologic toxicity was associated with pre-existing grade 3 or higher hematologic toxicity before PVRT (p = 0.03), and increased acute hematologic toxicity grade was associated with radiotherapy dose (p = 0.03).
- Grade 2 or higher neuropathy before PVRT was associated with acute grade 2 or higher neuropathy after PVRT (p = 0.001), but no unexpected toxicity signal was observed; pain, fatigue, diarrhea, and liver function abnormalities were not associated with acute or subacute toxicity.
CLINICAL TAKEAWAY
Concurrent radiotherapy with polatuzumab vedotin appears feasible in heavily pretreated relapsed or refractory aggressive B-cell lymphoma, including patients being bridged to additional therapy. The main practical caution is baseline marrow reserve: acute hematologic toxicity was strongly linked to pre-existing cytopenias and higher radiotherapy dose. Because this was a 21-patient retrospective series with heterogeneous disease, concurrent systemic therapy, and short follow-up, this is useful safety experience, not definitive guidance on sequencing or efficacy.