Ultra Low Dose Orbital Radiation Therapy in Treating Patients With Stage I-IV Indolent B-cell Lymphoma or Mantle Cell Lymphoma

PRIMARY OBJECTIVES: I. To evaluate the efficacy of ultra low dose 4 Gray (Gy) orbital radiation, measured as local orbital control (i.e. local control within the radiation field), in patients with limited and advanced stage low grade B lymphocyte (B cell) lymphoma and mantle cell lymphoma involving the ocular adnexa. II. To evaluate the efficacy of ultra low dose 4 Gy orbital radiation, measured as complete response, in patients with limited and advanced stage low grade B cell lymphoma and mantle cell lymphoma involving the ocular adnexa. III. To evaluate the acute and chronic toxicity of radiation to the orbit. SECONDARY OBJECTIVE: I. To determine if dynamic contrast enhanced magnetic resonance imaging can predict response to ultra low dose radiation therapy. OUTLINE: Patients undergo low dose orbital external beam radiation therapy (EBRT) on 2 consecutive days. Patients experiencing stable or progressive disease after 12-16 weeks of EBRT undergo additional low dose orbital EBRT over 10 fractions. Patients experiencing partial response or minimal response 1 year after EBRT also undergo low dose orbital EBRT over 10 fractions. After completion of study treatment, patients are followed up every 3-4 months for 6-8 months, every 6-12 months for up to 2 years, and then periodically thereafter.