Experience of two orbital MALT lymphomas treated with radiotherapy, and review of the literature.

Orbital MALT lymphoma is a relatively rare malignant disease, for which radiation therapy is effective. However, the optimal dose has not been determined. We experienced two cases of orbital MALT lymphoma. One patient was successfully treated, but the other developed a severe complication. We conclude that for safe treatment of orbital MALT lymphoma, a dose in excess of 40 Gy must not be delivered.