Appearance of monoclonal plasma cell diseases in whole‐body magnetic resonance imaging and correlation with parameters of disease activity

Abstract

The aim of our study was to assess in which way different infiltration patterns of monoclonal plasma cell diseases in wholebody (wb) magnetic resonance imaging (MRI) are associated with clinical stages, plasma cell content in bone marrow samples and established serum markers of disease activity. Institutional review board approval was obtained. We performed wb-MRI in 547 consecutive, unselected and untreated patients with monoclonal gammopathy of undetermined significance (MGUS, n 5 138), smoldering myeloma (SMM, n 5 157) and multiple myeloma (MM, n 5 252) on two 1.5 T MRI-scanners with body array coils. The studies were evaluated in consensus by two experienced radiologists blinded to the diagnosis. We observed focal lesions in 23.9% (MGUS), 34.4% (SMM) and 81.3% (MM), respectively. A diffuse infiltration pattern was detected in 38.4%, 45.9% and 71%, respectively. The differences between all infiltration patterns were significant (p < 0.0001). The presence of focal lesions and the presence of a diffuse bone marrow infiltration was associated with an increased plasma cell percentage in bone marrow samples (median 22% vs. 14%, 26% vs. 10%, both p < 0.0001) and monoclonal protein concentration (median 18 g/dl vs. 13 g/dl, p 5 0.003, 20 g/dl vs. 11 g/dl, p < 0.0001). Further categorization of the diffuse infiltration patterns in wb-MRI into "salt-and-pepper," moderate and severe identified significant associations with M-protein (median g/dl for S1P/moderate/severe 23/18/25, p 5 0.04), plasma cell percentage in the bone marrow (median 25%/24%/40%, p 5 0.02), and age (median years 67/60/57, p < 0.0001). Bone marrow infiltration in wb-MRI is significantly different between the various stages of plasma cell disease and correlates well with established markers of disease activity.Monoclonal plasma cell diseases like multiple myeloma (MM), monoclonal gammopathy of undetermined significance (MGUS) and smoldering myeloma (SMM) are a group of hematologic premalignant or malignant disorders associated with monoclonal proliferation of plasma cells mainly in the bone marrow.1,2 Although MGUS, being the most common disorder of plasma cells and occurring in 2% of persons older than 50 years, has an overall annual risk of progression of only 1% per year, the rate of transformation of SMM to MM or systemic amyloidosis (AL) has been shown to be 10% per year in the first 5 years. [3][4][5][6] In the aforementioned monoclonal plasma cell disorders, the bone marrow involvement may be present in different patterns: diffuse bone marrow infiltration and focal lesions. Diffuse bone marrow infiltration is characterized by malignant plasma cells, mixed up with normal bone marrow cells, still preserving the cancellous bone structure. Focal lesions are circumscribed solid foci of plasma cells with the potential of destruction of the cancellous and cortical bone.To image these changes, plain radiographs (PRs), computed tomography (CT) and magnetic resonance imaging (MRI) are currently in routine use. 7 Although PR has been an integral part of...

Whole-Body Low-Dose Computed Tomography and Advanced Imaging Techniques for Multiple Myeloma Bone Disease

“…MRI can provide distinct information compared with WBXR and CT, such as bone marrow infiltration and distinct patterns of marrow infiltrates that have been found to correlate with findings on bone marrow biopsy (17). A systematic review indicated that MRI has a superior focal lesion detection rate (as much as 82% higher) compared with WBXR (10).…”

Volumetry based biomarker speed of growth: Quantifying the change of total tumor volume in whole-body magnetic resonance imaging over time improves risk stratification of smoldering multiple myeloma patients

“…Approval had been received from the institutional ethics committee for retrospective analysis of imaging data from patients with monoclonal plasma cell disorders with waiver of informed consent. Parts of this cohort had been included in previous studies [ 6 , 10 , 24 – 26 ].…”

Imaging in myeloma with focus on advanced imaging techniques

“…MRI provides distinct information about the bone marrow and patterns of bone marrow infiltration which have been shown to correlate with bone marrow biopsy. 16 Different infiltration patterns (number of focal lesions and type of diffuse bone marrow infiltration) on WB-MRI (T 1 and STIR) have been reported to differ between the different stages of plasma cell disease (MGUS, smouldering myeloma and multiple myeloma) and correlate with M-protein and plasma cell percentage in bone marrow. 16 In addition, MRI spine is the first-line investigation for suspected spinal cord compression/ neural compromise.…”

“…16 Different infiltration patterns (number of focal lesions and type of diffuse bone marrow infiltration) on WB-MRI (T 1 and STIR) have been reported to differ between the different stages of plasma cell disease (MGUS, smouldering myeloma and multiple myeloma) and correlate with M-protein and plasma cell percentage in bone marrow. 16 In addition, MRI spine is the first-line investigation for suspected spinal cord compression/ neural compromise. MRI detects bone involvement in patients with myeloma much earlier than the myeloma-related bone destruction, with no radiation exposure.…”