1. Lymphoid Malignancies Branch, National Cancer Institute, National Institutes of Health, Bethesda, Maryland 20892, USA;
2. Biometric Research Branch, Division of Cancer Diagnosis and Treatment, National Cancer Institute, National Institutes of Health, Bethesda, Maryland 20892, USA
3. Office of Intramural Research, Center for Information Technology, National Institutes of Health, Bethesda, Maryland 20892, USA