Médecine Nucléaire et Radiothérapie

Utilization of Radioimmunotherapy (RIT) and Hematopoietic Stem Cell Transplantation (HSCT) in B-cell Non-Hodgkin’s Lymphoma (NHL): 10 Year Experience of a Single Community Cancer Center

Abstract

Nibal Saad, Kleanthe Kolizeras, Susan M Szpunar and Ayad Al-Katib

After Yttrium (Y⁹⁰) Ibritumomab tiuxetan (Zevalin) and Iodine (131I) tositumomab (Bexxar) were approved by the FDA, the improved response of B-cell NHL to this novel RIT makes it a promising alternative to more aggressive treatment like HSCT. In this study, we describe the experience of a single community-based cancer with RIT and HSCT in patients with B-cell NHL in terms of response, survival and toxicity. Retrospectively, we reviewed 75 patients with B cell NHL who were treated with either RIT (N=50) or HSCT (N=25) between 2003 and 2013. Choice of treatment modality, i.e. RIT vs. HSCT was based on discretion of treating Oncologist taking into consideration patient’s age, performance status, comorbidity and preferences. RIT-treated patients were older. HSCT was more likely to be used in aggressive lymphoma and as a consolidation of primary therapy. RIT was used mainly in indolent lymphoma and as salvage treatment. Overall response rates were better in HSCT-treated patients (100% vs. 76%). Median overall survival was higher in HSCT-treated patients (221 vs. 79.4 months). Similar results were obtained when we compared OS in patients younger than 60 years (221 vs. 79.4 months) and in patients with aggressive lymphoma (221 vs. 59.7 months). PFS was not met in HSCT, while it was 16.2 months in RIT. Myelodysplastic syndrome (MDS) occurred in both groups (12% HSCT vs. 2% RIT). Thrombocytopenia was more prevalent with RIT. All other toxicities were significantly more common with HSCT. This study shows that, in clinical practice, younger patients with aggressive B-cell NHL and without significant comorbidity are more likely to be offered HSCT. On the other hand, RIT was offered to older patients with indolent histology. Our results show that RIT is a reasonable alternative salvage treatment modality for B-cell NHL patients who are not candidates for HSCT.