ALB and plasma cell myeloma: In 2005 the International Myeloma Working Group (IMWG) developed a new stage system called the International Staging System (ISS), which was relying on the combinations of two easily available and objective prognostic variables (serum beta 2 microglobulin (Sβ2M) and serum albumin): ISS stage I, Sβ2M less than 3.5 mg/L plus serum albumin ≥3.5 g/dL; ISS stage II, neither stage I nor stage III; and ISS stage III, Sβ2M ≥ 5.5 mg/L [4] (Table 1).