Objectives: We evaluated whether staging with positron emission tomography (PET) or treatment with rituximab after involved-field radiation therapy (IFRT) results in an improved progression-free survival (PFS) for early-stage indolent non-Hodgkin lymphoma (NHL).
Methods: We identified 42 patients with stage I/II low-grade NHL treated with initial IFRT at our institution between 1992 and 2009, who had been staged with computed tomography (CT) or PET. A retrospective analysis was performed to evaluate PFS according to staging by CT or PET, and by receipt of rituximab after IFRT.
Results: Overall PFS was 68% and 61% at 5 and 10 years, respectively. There was no significant difference in PFS whether patients were staged by CT (n=17) or by PET (n=25), with 5-year PFS rates of 76% and 60%, respectively. Eleven patients received 4 weekly doses of rituximab after IFRT, with no improvement in 5-year PFS: 46% for rituximab-treated patients versus 72% for patients who were not given rituximab. However, more patients who were given rituximab were stage II.
Conclusions: Patients with limited stage indolent NHL staged with either CT or PET and treated with IFRT have favorable PFS compared with historical controls. The administration of 4 weekly doses of rituximab after IFRT did not improve PFS in these patients. The use of rituximab in this setting should be evaluated in a randomized prospective study.