Treatment Outcomes in Patients with Conjunctival Mucosa-Associated Lymphoid Tissue (MALT) Lymphoma

To report the outcomes of different therapies in patients with conjunctival mucosa-associated lymphoid tissue (MALT) lymphoma.

This retrospective study included patients diagnosed with conjunctival MALT lymphoma between August 2000 and April 2022. Patients were classified into three groups according to their treatment: an observation group, a radiation therapy (RT) group, and a rituximab group (rituximab with or without chemotherapy). We analyzed overall survival (OS), overall, local, and systemic relapse-free survival (RFS), and adverse events after treatment.

This study included 15 patients (22 eyes). The 10-year OS was 100%. The 2-, 5-, and 10-year overall RFS rates were 80.1%, 41.2%, and 41.2% in all patients, respectively. The 2- and 5-year local RFS rates in the observation group were 100% and 0%, respectively. The 2-, 5-, and 10-year local RFS rates were 87%, 87%, and 87% in the RT group and 83%, 67%, and 67% in the rituximab group, respectively. The 2- and 5-year systemic RFS rates in the observation group were both 100%, and the 2-, 5-, and 10-year systemic RFS rates were 92%, 55%, and 55% in the RT group, and 100%, 60%, and 60% in the rituximab group, respectively. After RT, 53.3% of the eyes developed cataracts and 75% of these were treated with cataract surgery. In addition, 53.3% of the eyes developed dry eyes and were treated with eye drops. Rituximab with or without chemotherapy resulted in some systemic adverse events, but these improved following symptomatic therapies.

RT resulted in good local control of conjunctival MALT lymphoma; however, systemic relapse may occur during long-term follow-up. Local and/or systemic relapse may also occur during long-term follow-up in patients treated by observation or rituximab with or without chemotherapy. Patients with conjunctival MALT lymphoma should be followed-up carefully for as long as possible after treatment.