RESUMEN
Central nervous system (CNS) involvement is a rare and aggressive complication of multiple myeloma (MM). We identified 54/4352 MM patients (1.2%), who developed CNS-MM between 2000 and 2022. A matched-control group of MM patients without CNS-MM was used for comparisons. Median age was 63 years. Median time to CNS-MM was 28 months; 6/54 experienced CNS-MM at MM diagnosis. Abnormal lactate dehydrogenase (LDH), high-risk cytogenetics, and extramedullary involvement (EMI), that is, soft tissue plasmacytomas and/or plasma cell leukemia (PCL), were more frequent in CNS-MM versus controls (p < .05); 13/54 had PCL at CNS-MM. The majority had leptomeningeal infiltration (LMI) (66%); 26% had CNS-MM without systemic myeloma; EMI was the strongest predictor for CNS-MM (OR: 6.3). Median overall survival (OS) of CNS-MM patients versus controls was 43 months (95% CI: 32-54) versus 60 months (95% CI: 38-82) (p < .001); treatment of CNS-MM included mainly bortezomib/thalidomide/chemotherapy whereas 20% received novel drugs/immunotherapy combinations; 28 patients underwent cerebrospinal fluid infusions; EMI was the strongest negative predictor for post CNS-MM OS (p = .005; HR: 2.9). Treatment after 2016 predicted significantly for OS (p = .002; HR: 0.27). Median post CNS-MM OS was 4 months (95% CI: 2.6-5.4); in patients treated after 2016 median OS was 12 months. In conclusion, we have demonstrated in this large real-world series that survival of CNS-MM remains poor; however, there is a positive impact of treatment after 2016, related to the efficacy of modern anti-myeloma therapy; EMI significantly increases the probability to develop CNS-MM and the risk of post CNS-MM death, indicating a potential need for CNS prophylaxis for those patients.
RESUMEN
We investigated incidence, characteristics and outcome of patients with macrofocal multiple myeloma (MFMM) treated mainly with novel therapies. Based on definition (BMPCs <20% and lytic lesions/plasmacytomas, without anemia, renal insufficiency or hypercalcemia) we identified 140 patients with MFMM, among 4650 myeloma patients (3%). Twice the number of patients with typical myeloma were used as controls; 60% were <65 years and 70% had advanced bone disease. Plasmacytomas were more frequent in MFMM compared with standard myeloma (68% vs 15%, P < .05). Adverse prognostic parameters (high lactate dehydrogenase, advanced stage, high risk cytogenetics, immunoparesis) were less common in patients with MFMM compared with controls (P < .05); 90% received novel agents and 47% underwent autologous transplantation upfront; 90% achieved an objective response; 70% had at least very good partial response which was significantly higher compared with controls (P < .05). After a median follow-up of 52 months, 33 patients have died. Early death (<12 months) was infrequent in MFMM. Median progression-free survival and overall survival (OS) were 46 and 129 months respectively, both significantly longer compared with controls (P < .001). Proteasome inhibitor (PI)-based therapy was the only independent predictor for OS in the multivariate analysis (HR: 3.9; P < .001). In conclusion, MFMM is a distinct entity presented in young and elderly subjects, characterized by limited bone marrow infiltration, advanced bone disease and frequent presence of plasmacytomas; MFMM patients have less often adverse prognostic features and achieve excellent responses and prolonged OS especially when treated with PI-based therapies. Novel imaging will help in a more accurate classification of this entity.