Molecular Imaging in Myeloma Precursor Disease

Abstract

Multiple myeloma (MM) is consistently preceded by its pre-malignant states, monoclonal gammopathy of undetermined significance (MGUS) and/or smoldering multiple myeloma (SMM). By definition, precursor conditions do not exhibit end-organ disease (anemia, hypercalcemia, renal failure, skeletal lytic lesions, or a combination of these). However, new imaging methods are demonstrating that some patients in the MGUS or SNM category are exhibiting early signs of MM. Although MGUS/SMM patients are currently defined as low-risk versus high-risk based on clinical markers, we currently lack the ability to predict the individual patient’s risk of progression from MGUS/SMM to MM. Given that the presence of gross lytic bone lesions is a hallmark of MM, it is reasonable to believe that less severe bone changes defined by more sensitive imaging may be predictive of MM progression. Indeed, since bone disease is such an essential aspect of MM, imaging techniques directed at the detection of early bone lesions, have the potential to become increasingly more useful in the setting of MGUS/SMM. Current guidelines for the radiological assessment of MM still recommend the traditional skeletal survey, although its limitations are well-documented, especially in early phases of the disease when radiographs can significantly underestimate the extent of bone lesions and bone marrow involvement. Newer, more advanced imaging modalities, with higher sensitivities, including whole-body low-dose computed tomography (CT), magnetic resonance imaging (MRI) and positron emission tomography (PET) are being employed. Also various imaging techniques have been used to provide an assessment of bone involvement and identify extra-osseous disease. This review emphasizes the current state of the art and emerging imaging methods, which may help to better define high-risk versus low-risk MGUS/SMM. Ultimately, improved imaging could allow more tailored clinical management, and, most likely play an important role in the development of future treatment strategies for high-risk precursor disease.

Dynamic Contrast-Enhanced Magnetic Resonance Imaging for Assessment of Antiangiogenic Treatment Effects in Multiple Myeloma

“…Imaging treatment response in multiple myeloma is challenging because morphologic changes of existing bone lesions seldom occur after therapy (29). With our study, we were able to assess treatment response based on quantitative parameters, which is less influenced by interobserver variability than morphologic evaluation of osteolyses.…”

Does My Patient with a Serum Monoclonal Spike have Multiple Myeloma?

“…Active disease will appear as FDG-avid bone marrow uptake. 37 Its use is recommended if a strong suspicion for lytic lesions or pathologic fractures is present but standard radiologic studies are negative. MRI and PET-CT are useful techniques to evaluate solitary plasmacytoma and CT-guided biopsy of these lesions should be obtained, whenever possible, to provide a definitive diagnosis.…”

A voluminous mass as an initial clinical symptom of multiple myeloma: A case report

“…A traditional skeletal survey forms part of the standard of care for the staging and follow-up of bone lesions in patients with MM (10), and enables the identification of osteolytic lesions. In addition, CT examinations are commonly used to visualize the areas that are unable to be observed well on conventional radiographs, and may also be used to characterize soft tissue involvement (11). However, CT observations for MM are non-specific; thus, CT examinations may be used to guide a needle biopsy for histological diagnosis.…”

“…In T1-weighted imaging, bone myeloma lesions appear hypointense, while the lesions are visualized as hyperintense on T2-weighted imaging. Furthermore, bone myeloma lesions appear hyperintense in short T1 inversion recovery imaging and enhanced on post-contrast T1 sequences (11). PET is a non-invasive functional imaging technique that enables whole-body screening in a single procedure.…”