Catholic University of Korea, College of Medicine, Seoul St. Mary's Hospital, Lymphoma Group, Department of Hematology, Catholic University of Korea, College of Medicine, Seoul St. Mary's Hospital, Lymphoma Group, Department of Ophthalmology, Catholic University of Korea, College of Medicine, Seoul St. Mary's Hospital, Lymphoma Group, Department of Radiation Oncology, Catholic University of Korea, College of Medicine, Seoul St. Mary's Hospital, Lymphoma Group, Department of Radiology, Catholic University of Korea, College of Medicine, Seoul St. Mary's Hospital, Lymphoma Group, Department of Pathology, Catholic University of Korea - Department of Nuclear Medicine, Catholic University of Korea, College of Medicine, Seoul St. Mary's Hospital, Lymphoma Group, Department of Ophthalmology and Catholic University of Korea, College of Medicine, Seoul St. Mary's Hospital, Lymphoma Group, Department of Hematology