Purpose: To report our institution's treatment techniques, disease outcomes, and complication rates after radiotherapy for the management of lymphoma involving the orbits.
Patients and methods: We retrospectively reviewed the medical records of 44 patients curatively treated with radiotherapy for stage IAE (75%) or stage IIAE (25%) orbital lymphoma between 1969 and 2013. Median follow-up was 4.9 years. Thirty-eight patients (86%) had low-grade lymphoma and 6 (14%) had high-grade lymphoma. Radiation was delivered with either a wedge-pair (61%), single-anterior (34%), or anterior with bilateral wedges (5%) technique. The median radiation dose was 25.5 Gy (range, 15 to 47.5 Gy). Lens shielding was performed when possible. Cause-specific survival and freedom from distant relapse were calculated using the Kaplan-Meier method.
Results: The 5-year local control rate was 98%. Control of disease in the orbit was achieved in all but 1 patient who developed an out-of-field recurrence after irradiation of a lacrimal tumor. The 5-year regional control rate was 91% (3 patients failed in the contralateral orbit and 1 patient failed in the ipsilateral parotid). Freedom from disease, cause-specific survival, and overall survival rates at 5 and 10 years were 70% and 55%, 89% and 89%, and 76% and 61%, respectively. Acute toxicity was minimal. Ten patients (23%) reported worsened vision following radiotherapy, and cataracts developed in 17 patients. Cataracts developed in 13 of 28 patients treated without lens shielding (46%) and 4 of 16 patients (25%) treated with lens shielding.
Conclusion: Radiotherapy is a safe and effective local treatment in the management of orbital lymphoma.