Radiotherapy for orbital lymphoma : outcome and late effects

To analyze the effectiveness of radiotherapy in the management of orbital non-Hodgkin's lymphoma (NHL). 42 patients (median age 64.5 years) were reviewed retrospectively. The median follow-up period was 58 months. 26 patients had stage IE orbital lymphoma (22 indolent, four aggressive NHLs). 16 patients had advanced NHLs in stages II-IV with orbital involvement (eleven indolent, five aggressive NHLs). The median radiation dose was 40 Gy (20-46 Gy) for indolent lymphoma and 44 Gy (20-48 Gy) for aggressive lymphoma. Patients with stage IE were treated with at least 30 Gy. The 5-year local control rate for patients with stage I was 100%, the 5-year overall survival 91%. Two distant relapses were found, but no lymphoma-related death was detected. The 5-year local control rate for patients in stages II, III, and IV was 80%. Two local failures were detected. The 5-year overall survival for the advanced stages was 47%, nine patients with stages III and IV died due to systemic progression of lymphoma. Acute, radiotherapy-related complications grade 3/4 were not observed. Late effects grade 1/2 were documented in 45%. Six patients, treated with doses of > 36 Gy, developed grade 3 complications (four cataract, two dryness). Radiotherapy alone yields excellent local control and overall survival rates in orbital lymphoma stage IE. Local irradiation is also well tolerated and effective in advanced NHL stages with orbital infiltration. Doses of > 36 Gy resulted in an increase of late complications.