Consolidation of first remission using radioimmunotherapy with yttrium-90-ibritumomab-tiuxetan in adult patients with Burkitt lymphoma

• Radioimmunotherapy consolidation has not been reported in rituximab treated BL.
• In this series, none of 5 BL patients relapsed after Y-90-IT consolidation in CR1.
• OS and PFS in BL patients without or with Y-90-IT were not significant.
• Significant myelosuppression was seen in BL patients after Y-90-IT consolidation.

The addition of anti-CD20 antibodies to high intensity polychemotherapy regimens has improved response and survival rates in newly diagnosed patients with Burkitt lymphoma (BL). However, the role of additional anti-CD20 directed radioimmunotherapy for consolidation of first remission (CR1) has not been reported so far in BL patients receiving rituximab during first-line treatment. We compared five BL patients receiving Y-90-IT radioimmunotherapy consolidation in CR1 to 22 consecutive BL patients without consolidation. We observed that Y-90-IT treatment was associated with clinically relevant myelosuppression. After a median follow-up of 50 months, none of the patients with Y-90-IT treatment relapsed, and no patient died. In contrast, one patient (4.5%) in the non-Y-90-IT group relapsed (50 months-PFS 95.5%; p = 0.6336), and one patient died (50 months-OS 95.5%; p = 0.6171). In conclusion, our data suggest that survival rates are excellent and equal in rituximab pretreated BL patients with or without Y-90-IT consolidation in first remission.