TTP in MGUS and SMM according to the score system. (A) The score system for MGUS was built on the basis of the percentage of immunophenotypically aberrant PC within the BMPC compartment (< 95% aberrant PC, score of 0; ≥ 95%, score of 1) and DNA index: aneuploid (score of 1) or diploid (score of 0). In patients with a score of 1, the median TTP has not been reached; in patients with a score of 2, the median TTP is 120 months; and in patients with a score of 3, the median PFS is 61 months (P < .001). (B) The score system for SMM was built on the basis of the percentage of immunophenotypically aberrant PC within the BMPC compartment (< 95% aberrant PC, score of 0; ≥ 95%, score of 1) and the presence (score of 1) or absence (score of 0) of immunoparesis. In patients with a score of 1, the median TTP has not been reached; in patients with a score of 2, the median TTP is 73 months; and in patients with a score of 3, the median TTP is 23 months (P < .001).