Practical considerations – Type of sample

A further consideration is whether to obtain blood or bone marrow for testing. Patients generally prefer peripheral blood testing because it is less invasive and less painful than bone marrow aspiration. However, blood cell production (haematopoiesis) begins in stem cells in the bone marrow, and it takes a while for cells to mobilise to the peripheral blood. A bone marrow sample may therefore give an earlier snapshot into disease status, allowing earlier detection of a molecular relapse.