[Clinical Analysis of 46 Cases of Multiple Myeloma with Extramedullary Disease].

Objective: To investigate the effect of clinical baseline data on prognosis in patients with multiple myeloma (MM) complicated by extramedullary disease (EMD).

Methods: The clinical data of 46 MM patients with EMD were retrospectively analyzed. The clinical data and survival prognosis of MM patients in primary EMD group and recurrent EMD group were analyzed. The classified baseline data were expressed by the number of cases (percentage), the χ test was used to compare the two classification data groups. The OS and PFS curves were drawn by multiplication positive limit method (Kaplan-Meier). Log-rank test was used for the univariate analysis of prognosis, and COX proportional risk regression model was used for the multiple factors of prognosis.

Results: β microglobulin≥2.7 g/L, lactic dehydrogenase≥250 U/L, serum calcium≥2.75 mmol/L, plasma cells in bone marrow≥60% were the poor prognostic factors for PFS. Serum calcium≥2.75 mmol/L and the plasma cells in bone marrow≥60% were the poor prognostic factors for OS. Multivariate regression analysis enroling the statistically significant factors in univariate analysis baseline date in factors in showed that plasma cell level≥60% in bone marrow was independent poor prognostic factors for PFS, and serum calcium≥2.75 mmol/L was an independent poor prognostic factor for OS. The IgG type is the most common type of MM complicated by EMD. The remission depth of primary EMD group≥VGPR was lower than that of recurrent EMD group, and there was significant difference between the two groups (P<0.05), and the median OS time of patients with primary EMD group was shorter than that of patients with recurrent EMD group, the difference was statistically significant (P<0.05). The 3-year survival rates of primary EMD group and recurrent EMD group were 10.0% and 34%, respectively, there was no significant difference between the two groups (P>0.05). The 5-year survival rate was 0 and 20%, respectively, there was significant difference between the two groups (P<0.05).

Conclusion: The remission depth of primary EMD group≥VGPR is lower than that of recurrent EMD group，and the OS time of patients in primary EMD group is shorter than that in recurrent EMD group. Bortezomib-based chemotherapy could not improve the prognosis of patients with primary EMD and recurrent EMD, and the prognosis of patients with primary EMD is even worse.