Low-Dose Radiation Therapy for Primary Conjunctival Marginal Zone B-Cell Lymphoma

PURPOSE: The purpose of this study was to evaluate the clinical features and the long-term outcomes of primary conjunctival marginal zone B-cell lymphoma (MZBCL) patients who were treated with radiation therapy (RT). MATERIALS AND METHODS: Retrospective data of 79 patients with 121 primary conjunctival MZBCL lesions were collected from January 1, 2001 till June 30, 2014. All lesions were treated by local RT (26 Gy) with patient-specific customized lens-shielding device. RESULTS: The current Korean patients’ cohort showed younger median age at diagnosis (38 years), great female preponderance (78.5%) and more frequent bilateral involvement (53.2%) than the previous studies. Following 26 Gy’s RT, excellent clinical outcomes were achieved: 5-year rates of overall survival, local relapse-free survival, and contralateral relapse-free survival were 100%, 98.1%, and 91.5%, respectively. Two patients (2.5%) developed local relapse and five (6.3%) developed relapse at initially uninvolved contralateral conjunctiva with median interval of 52.9 months, and late adverse events of grade 2 and 3 occurred in seven (8.8%) and two (2.5%) patients, respectively. CONCLUSION: 26 Gy’s RT was highly effective and safe, with the use of lens-shielding device, in treating patients with primary conjunctival MZBCL.