Radiotherapy for Extranodal, Marginal Zone, B-cell Lymphoma of Mucosa-associated Lymphoid Tissue Originating in the Ocular Adnexa: a Multiinstitutional, Retrospective Review of 50 Patients

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 multiinstitutional, retrospective study was performed on 50 patients with Stage IE ocular-adnexal MALT lymphoma who were treated with radiotherapy between 1989 and 1999. The impact of patient characteristics and other variables on tumor control was analyzed.

Results: Responses to radiotherapy include a complete response (CR) in 26 patients, a partial response (PR) in 20 patients, and no change in 4 patients. Forty-nine of 50 patients obtained tumor control in the ocular adnexa at 24 months. Overall, 6 patients exhibited disease recurrence at 4-97 months. Three patients developed recurrence in the ocular adnexa. Two patients had isolated extranodal failure involving the oral floor and the submandibular gland, and one patient experienced failure in the neck lymph node. The initial tumor response had a marginal impact on the development of recurrence. None of the 26 patients who achieved a CR experienced ocular-adnexal recurrence. All three patients who experienced local treatment failure belonged to the initial PR group. In total, five of six 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 rate was 91% with a median follow-up of 46 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.