Clinical Study On Radiotherapy For Mucosa-associated Lymphoid Tissue Lymphoma Of The Ocular Adnexa

BACKGROUND:Due to the small number of patients and differences in the pathologic classification in most radiotherapy series, information regarding the adequacy of tumor control in patients with ocular-adnexal marginal zone B-cell lymphoma of mucosa-associated lymphoid tissue (MALT lymphoma) is limited.METHODS:A retrospective study was performed on 68 patients with Stage IE ocular adnexal MALT lymphoma who were treated with radiotherapy between 1997 and 2008. The impact of patient characteristics and other variables on tumor control was analyzed.RESULTS.:Responses to radiotherapy include a complete response (CR) in 43 patients, a partial response (PR) in 25 patients. Sixty-six of 68 patients obtained tumor control in the ocular adnexa at 24 months. Overall,9 patients exhibited disease recurrence at 4-97 months. Four patients developed recurrence in the ocular adnexa. Two patients had isolated extranodal failure involving the the submandibular gland and stomach, and one patient experienced failure in the neck lymph node, and one patient failure in the preauricular lymph nodes. The initial tumor response had a marginal impact on the development of recurrence. None of the 43 patients who achieved a CR experienced ocular-adnexal recurrence. All four patients who experienced local treatment failure belonged to the initial PR group.In total, eight of nine patients who developed recurrent disease had obtained a PR after initial radiotherapy. Age, gender, tumor location, and dose of radiotherapy did not influence the development of recurrence.There was only one death due to lymphoma. The 5-year overall survival, relapse-free survival and cause-specific survival were 91.3%, 94.4% and 87.6%, respectively with a median follow-up of 55 months.CONCLUSIONS.:Radiotherapy offers excellent local control with a prolonged clinical course for patients with MALT lymphoma in the ocular adnexa. The initial response to radiotherapy marginally influenced the probability of recurrence. We suggest that a dose of 30 Gy is tolerable and sufficient for treating orbital MALT lymphoma. Even following recurrence, successful salvage is possible with RT or chemotherapy.