Long-term outcomes of primary ocular adnexal lymphoma treatment with intraorbital rituximab injections

We recently reported on the efficacy of intralesional rituximab for treating primary ocular adnexal lymphoma in a pilot study. After treatment, a complete response was observed in two of five patients, a partial response in one patient, and lesion recurrence in two patients. In this study, we evaluate the long-term follow-up of the five previously treated patients as well as the response of two new patients to an augmented dose of rituximab. We followed up the five patients who were treated with rituximab during the initial pilot study. Two additional patients were also enrolled and treated with four intraorbital injections of 10 mg rituximab once a week for 1 month (total dose of 40 mg). Median follow-up period was 4 years for the first five patients and 1 year for the last two patients. Lymphoma did not relapse in the two patients who originally responded immediately to treatment. Of the initial partial responders, one became disease-free after additional rituximab treatment, and one experienced a standardized uptake value reduction, as measured with positron emission tomography-CT. One patient who experienced abdominal and pulmonary localization 7 months later showed no local recurrence. The two newly enrolled patients had complete remission after the first cycle of treatment and no disease recurrence eight and 11 months later, respectively. This study suggests that intralesional administration of rituximab for treating localized ocular adnexal CD20+ lymphomas could be an effective front-line therapeutic option with negligible side effects and a good response rate and duration.