PurposePrimary ocular adnexal lymphomas are cured by radiotherapy; however, complications are frequent and relapses may occur. In this case, we aimed to report the efficacy and safety of extended systemic rituximab (anti-CD 20 monoclonal antibody) therapy of conjunctival mucosa-associated lymphoid tissue (MALT) lymphoma.MethodsIn the standard regimen, rituximab is used as four consecutive weekly infusions of 375mg/m(2) in patients with low-grade lymphomas. We treated a patient who had bilateral conjunctival MALT lymphoma with rituximab 375mg/m(2) intravenously once weekly for 10weeks as a first-line therapy.ResultsDuring the examination of the sixth week, we observed partial response of the lesions in both eyes. At the end of the tenth cure, complete remission was achieved. No local or systemic adverse effect was observed. The patient has no signs of recurrence during the 22-months follow-up period.ConclusionExtended rituximab therapy may be an effective and well-tolerated first-line treatment option for bilateral conjunctival MALT lymphoma.