Collect blood or bone marrow in a lavender top tube. Refrigerate and send intact blood or bone marrow specimen within 48 hours of collection. Fresh tissue (preferably 0.5cm3, sent in RPMI) and fresh aspirates or body fluids are acceptable. Refrigerate and send, preferably within 24 hours. Frozen tissue specimens – preferably frozen with 1 hour of collection – may also be sent frozen on dry ice. Fresh cell suspensions in RPMI should be refrigerated and sent, preferably within 48 hours. Frozen cell suspensions – preferably frozen with 1 hour of collection – may also be sent frozen on dry ice. Fixed cytogenetic cell suspensions or pellets in Carnoy’s fixative. Refrigerate and send. For formalin-fixed, paraffin-embedded tissue, a tissue block is preferred. Unstained, UNBAKED slides (5-8, 10-micron slides; 10-15 if few neoplastic cells are present) with associated H&E stained slide are also acceptable. Decalcified tissue or other fixatives will be accepted and the assay attempted, however these may result in failed testing due to degraded nucleic acid. Both blocks and slides should be stored at room temperature.