Abstract
Involved-site radiation therapy is effective for curative and palliative treatments of cancers, including lymphoma. This case study describes the use of whole-eye radiation for primary intraocular lymphoma occurring during primary central nervous system lymphoma. The patient, a 68-year-old man, developed personality changes and apathy two weeks after cataract surgery combined with vitrectomy for vitreous opacity in the left eye. Magnetic resonance imaging revealed a mass lesion in the left frontal lobe, and biopsy by craniotomy confirmed diffuse large B-cell lymphoma. He underwent chemotherapy using rituximab combined with high-dose methotrexate and high-dose cytarabine in association with intrathecal methotrexate and cytarabine injections, leading to complete remission. At age 75, he noticed forgetfulness, and fluorodeoxyglucose positron emission tomography and magnetic resonance imaging revealed a relapse of lymphoma in the splenium of the corpus callosum. He underwent chemotherapy using rituximab combined with high-dose methotrexate, followed by monthly rituximab monotherapy for one year and then rituximab monotherapy every two months for one year. He maintained complete remission with no treatment until age 78, when he developed subretinal choroidal lesions in the left eye and underwent whole-eye radiation at 40 Gy. One year later, he developed subretinal choroidal lesions in the right eye and underwent whole-eye radiation at 40 Gy. At age 81, he had lower limb weakness with disorientation. Magnetic resonance imaging showed a relapse of lymphoma in the right frontal to temporal lobe. The brain lesions showed a marked response to four weeks of oral tirabrutinib as a salvage therapy, but the lesions regrew, and the patient died seven months later. Throughout the treatment, he maintained a visual acuity of 0.7 (decimal scale) in both eyes. In conclusion, whole-eye radiation should be considered as a treatment option for the local control of active intraocular lymphoma, especially choroidal lesions, for patients with primary central nervous system lymphoma with no active brain lesions and without systemic treatment.