CD38 is expressed at high levels primarily in plasma cell neoplasms and to a certain degree in normal lymphoid and non-hematopoietic cells.10 CD38 is a transmembrane glycoprotein with an ectoenzyme function and is involved in NAD+ metabolism leading to intracellular calcium homeostasis necessary for cell survival.10, 11 CD38 can also bind to CD31 and thereby act as an adhesion molecule or a receptor, although this process is not fully understood.12,13. Here, CD38 is linked to plasma cell neoplasm.