MRI negative meningeal myeloma with abducens nerve palsies responding to intrathecal chemotherapy

Sixth Nerve Palsy From Multiple Myeloma in Central Nervous System: Case Series and Review of Current Literature

We reported two cases of the central nervous system (CNS) multiple myeloma (MM) with unusual presentation of sixth nerve palsy. The first patient developed in the setting of newly diagnosed MM and the second patient in the relapsed refractory setting. One underwent surgery, and the other received radiation. Both patients received systemic chemotherapy and noted improvement. We also performed a comprehensive literature review of previously published cases of sixth nerve palsy from MM. This review highlights the importance of recognizing this presentation of CNS multiple myeloma to avoid delays in diagnosis and to get appropriate management in time.

Diagnostic Advances in Multiple Myeloma

There have been several advances in the diagnosis of multiple myeloma (MM) in recent years. Serum free light chains have improved the ability to diagnose light chain MM; however, there are still difficulties in the serologic diagnosis of MM in some cases, particularly IgA MM. A novel heavy/light chain assay is able to improve the accuracy of diagnosis in these cases. Free light chains may also improve the diagnosis of extramedullary disease in difficult cases such as disease involving the central nervous system, pleura, or ascites. Advances in imaging such as whole body low-dose computed tomography (CT) whole body magnetic resonance imaging (MRI), and positron emission tomography/computed tomography (PET/CT) have improved sensitivity in identifying lytic bone lesions, which would enable earlier treatment, and monitoring of osseous disease particularly in non- or oligosecretory disease. New techniques such as fused PET/MRI may further enhance the diagnosis of both bone lesions and extramedullary disease.

Central nervous system involvement by multiple myeloma: A multi-institutional retrospective study of 172 patients in daily clinical practice

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. © 2016 Wiley Periodicals, Inc.