K. SAMPLE PROCESSING: Centralized screening will be employed at Princess Margaret Hospital. Following informed consent site should send two fresh heparinized (green top tube) marrow samples (5cc per tube or best available) by overnight courier (see Appendix VI for shipping and notification instructions) for t4;14 screening test. Tri-color fluorescence in situ hybridization (FISH) for t(4;14) will be performed and reported back to referring site within 5-7 working days.