The multicenter retrospective study conducted in 38 centers from 20 countries including 172 adult patients with CNS MM aimed to describe the clinical and pathological characteristics and outcomes of patients with multiple myeloma (MM) involving the central nervous system (CNS). Univariate and multivariate analyses were performed to identify prognostic factors for survival. The median time from MM diagnosis to CNS MM diagnosis was 3 years. Thirty‐eight patients (22%) were diagnosed with CNS involvement at the time of initial MM diagnosis and 134 (78%) at relapse/progression. Upon diagnosis of CNS MM, 97% patients received initial therapy for CNS disease, of which 76% received systemic therapy, 36% radiotherapy and 32% intrathecal therapy. After a median follow‐up of 3.5 years, the median overall survival (OS) from the onset of CNS involvement for the entire group was 7 months. Untreated and treated patients had median OS of 2 and 8 months, respectively (P < 0.001). At least one previous line of therapy for MM before the diagnosis of CNS disease and >1 cytogenetic abnormality detected by FISH were independently associated with worse OS. The median OS for patients with 0, 1 and 2 of these risk factors were 25 months, 5.5 months and 2 months, respectively (P < 0.001). Neurological manifestations, not considered chemotherapy‐related, observed at any time after initial diagnosis of MM should raise a suspicion of CNS involvement. Although prognosis is generally poor, the survival of previously untreated patients and patients with favorable cytogenetic profile might be prolonged due to systemic treatment and/or radiotherapy. Am. J. Hematol. 91:575–580, 2016.

BACKGROUND: Intracranial involvement in multiple myeloma is extremely rare. The effect of new drugs (eg, thalidomide, bortezomib, lenalidomide) with respect to old drugs (eg, alkylators, steroids) has not been reported.METHODS: We collected clinical and biological data of patients presenting with an osteo‐dural or primary dural multiple myeloma (OD‐DMM) or a central nervous system myelomatosis (CNS‐MM) by sending a questionnaire to the centers of the Gruppo Italiano Malattie Ematologiche dell'Adulto (GIMEMA).RESULTS: A total of 50 patients were registered. New therapies were used in 35 patients, whereas 15 patients received old treatments. Twenty‐five out of 50 patients obtained a complete remission or a very good partial remission (CR+VGPR). Overall survival (OS) for CNS‐MM was 6 months, for OD‐DMM 25 months. OS was 25 months for patients treated with new agents versus 8 months with old agents. Improved OS and progression‐free survival were predicted by response (CR+VGPR) and by patients who underwent stem cell transplantation versus chemotherapy. β2‐Microglobulin >5 mmol/L was a poor prognostic factor. Multivariate analysis showed poor survival for patients with β2‐microglobulin >5 mmol/L and better survival for patients achieving CR+VGPR.CONCLUSIONS: The overall data highlight the relevance of therapy with new drugs in intracranial myeloma, providing a framework for future clinical trials. Cancer 2011;. © 2011 American Cancer Society.