Pilot trial of yttrium-90 ibritumomab tiuxetan consolidation following rituximab, cyclophosphamide, doxorubicin, vincristine and prednisolone chemotherapy in patients with limited-stage, bulky diffuse large B-cell lymphoma

The clinical efficacy and safety of yttrium-90 ( ⁹⁰Y)-ibritumomab tiuxetan consolidation treatment following rituximab, cyclophosphamide, doxorubicin, vincristine and prednisolone (R-CHOP) chemotherapy was investigated in patients with limited-stage and bulky diffuse large B-cell lymphoma (DLBCL). This prospective, multi-center, pilot trial included 21 patients who were newly diagnosed with stage I/II, bulky DLBCL and achieved a complete or partial response after six cycles of R-CHOP. The median size of bulky disease was 10.0 × 7.0 cm. After a median follow-up of 28.8 months, the overall response rate after ⁹⁰Y-ibritumomab tiuxetan consolidation treatment was 80.9%, including 4.8% partial response. However, six patients (28.6%) experienced a progression or relapse. The 3-year overall and progression-free survival rates were 85.0 ± 8.0% and 75.0 ± 9.7%, respectively. Grade 34 adverse events were mainly hematologic toxicities, such as thrombocytopenia (35%) and neutropenia (60%). One patient experienced grade 3 Pneumocystis carinii pneumonitis. Thus, ⁹⁰Y-ibritumomab tiuxetan consolidation following six cycles of R-CHOP resulted in an acceptable response with tolerable toxicity in patients with limited-stage and bulky DLBCL.