Early monoclonal protein decline pattern is an independent prognostic factor in patients with multiple myeloma

Patients always have different responses to the same treatment due to the heterogeneity of multiple myeloma (MM). However, the relationship between monoclonal protein (M-protein) reduction rates during treatment and survival prognosis in MM patients remains controversial. We retrospectively analyzed 198 newly diagnosed MM patients who received regular bortezomib-based chemotherapy for at least 2 cycles and subsequent autologous stem cell transplantation (ASCT) plus continuous maintenance. The relationship between the early M-protein reduction rates and survival prognosis was evaluated. This study is the first to divide patients into three patterns, namely, A, B, and C, according to the M-protein reduction rate during the first two therapy cycles. The results showed that pattern B patients with progressive reduction in M-protein had better progression-free survival (PFS) and overall survival (OS) than did pattern A or C patients with precipitating or slow M-protein reduction (75.33 ± 18.81 versus 41.23 ± 9.13 or 26.60 ± 6.67 months; P < 0.001; 117.33 ± 18.44 versus 71.00 ± 10.06 or 39.73 ± 24.10 months; P = 0.003, respectively). In addition, biological analysis showed that pattern A + C patients had higher international staging system (ISS) stage III proportions (P = 0.008) and lactate dehydrogenase (LDH) elevations (P = 0.044) than pattern B patients. Furthermore, pattern A + C was a significant independent adverse parameter for PFS and OS (HR = 2.62, P = 0.001; HR = 2.15, P = 0.022, respectively). Thus, our results demonstrate that pattern A + C indicates an inferior survival prognosis in MM.