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).
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.
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.
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.