Imaging in myeloma with focus on advanced imaging techniques

Review of whole-body magnetic resonance imaging in multiple myeloma

Multiple Myeloma (MM) is a hematological malignancy affecting bone marrow, most frequently in elderly men. Imaging has a crucial role in this disease. Recently, whole-body MRI has been introduced and it has gained growing interest due to is high sensitivity and specificity in evaluating bone marrow involvement in MM. Diffusion-weighted sequences (DWI) with apparent diffusion coefficient (ADC) maps have emerged as the most sensitive technique to evaluate patients with MM, both in the pre- and post-treatment setting. Aim of this review is to provide an overview of the role and main imaging findings of whole-body MRI in MM.

Photon Counting Detector Computed Tomography: A New Frontier of Myeloma Bone Disease Evaluation

Photon counting detector (PCD) computed tomography (CT) is a paradigm-shifting innovation in CT imaging which was recently granted approval for clinical use by the US Food and Drug Administration. PCD-CT allows the generation of multi-energy images with increased contrast and scanning speed or ultra-high spatial resolution (UHR) images with lower radiation doses, compared to the currently used energy integrating detector (EID) CT. Since the recognition of bone disease related to multiple myeloma is important for the diagnosis and management of patients, the advent of PCD-CT heralds a new era in superior diagnostic evaluation of myeloma bone disease. In a first-in-human pilot study, patients with multiple myeloma were imaged with UHR-PCD-CT to validate and establish the utility of this technology in routine imaging and clinical care. We describe 2 cases from that cohort to highlight the superior imaging performance and diagnostic potential of PCD-CT for multiple myeloma compared to clinical standard EID-CT. We also discuss how the advanced imaging capabilities from PCD-CT enhances clinical diagnostics to improve care and overall outcomes for patients.

Deep Learning for Automatic Bone Marrow Apparent Diffusion Coefficient Measurements From Whole-Body Magnetic Resonance Imaging in Patients With Multiple Myeloma: A Retrospective Multicenter Study

OBJECTIVES

Diffusion-weighted magnetic resonance imaging (MRI) is increasingly important in patients with multiple myeloma (MM). The objective of this study was to train and test an algorithm for automatic pelvic bone marrow analysis from whole-body apparent diffusion coefficient (ADC) maps in patients with MM, which automatically segments pelvic bones and subsequently extracts objective, representative ADC measurements from each bone.

MATERIALS AND METHODS

In this retrospective multicentric study, 180 MRIs from 54 patients were annotated (semi)manually and used to train an nnU-Net for automatic, individual segmentation of the right hip bone, the left hip bone, and the sacral bone. The quality of the automatic segmentation was evaluated on 15 manually segmented whole-body MRIs from 3 centers using the dice score. In 3 independent test sets from 3 centers, which comprised a total of 312 whole-body MRIs, agreement between automatically extracted mean ADC values from the nnU-Net segmentation and manual ADC measurements from 2 independent radiologists was evaluated. Bland-Altman plots were constructed, and absolute bias, relative bias to mean, limits of agreement, and coefficients of variation were calculated. In 56 patients with newly diagnosed MM who had undergone bone marrow biopsy, ADC measurements were correlated with biopsy results using Spearman correlation.

RESULTS

The ADC-nnU-Net achieved automatic segmentations with mean dice scores of 0.92, 0.93, and 0.85 for the right pelvis, the left pelvis, and the sacral bone, whereas the interrater experiment gave mean dice scores of 0.86, 0.86, and 0.77, respectively. The agreement between radiologists' manual ADC measurements and automatic ADC measurements was as follows: the bias between the first reader and the automatic approach was 49 × 10 -6 mm 2 /s, 7 × 10 -6 mm 2 /s, and -58 × 10 -6 mm 2 /s, and the bias between the second reader and the automatic approach was 12 × 10 -6 mm 2 /s, 2 × 10 -6 mm 2 /s, and -66 × 10 -6 mm 2 /s for the right pelvis, the left pelvis, and the sacral bone, respectively. The bias between reader 1 and reader 2 was 40 × 10 -6 mm 2 /s, 8 × 10 -6 mm 2 /s, and 7 × 10 -6 mm 2 /s, and the mean absolute difference between manual readers was 84 × 10 -6 mm 2 /s, 65 × 10 -6 mm 2 /s, and 75 × 10 -6 mm 2 /s. Automatically extracted ADC values significantly correlated with bone marrow plasma cell infiltration ( R = 0.36, P = 0.007).

CONCLUSIONS

In this study, a nnU-Net was trained that can automatically segment pelvic bone marrow from whole-body ADC maps in multicentric data sets with a quality comparable to manual segmentations. This approach allows automatic, objective bone marrow ADC measurements, which agree well with manual ADC measurements and can help to overcome interrater variability or nonrepresentative measurements. Automatically extracted ADC values significantly correlate with bone marrow plasma cell infiltration and might be of value for automatic staging, risk stratification, or therapy response assessment.

Functional Imaging in the Evaluation of Treatment Response in Multiple Myeloma: The Role of PET-CT and MRI

Bone disease is among the defining characteristics of symptomatic Multiple Myeloma (MM). Imaging techniques such as fluorodeoxyglucose positron emission tomography-computed tomography (FDG PET/CT) and magnetic resonance imaging (MRI) can identify plasma cell proliferation and quantify disease activity. This function renders these imaging tools as suitable not only for diagnosis, but also for the assessment of bone disease after treatment of MM patients. The aim of this article is to review FDG PET/CT and MRI and their applications, with a focus on their role in treatment response evaluation. MRI emerges as the technique with the highest sensitivity in lesions' detection and PET/CT as the technique with a major impact on prognosis. Their comparison yields different results concerning the best tool to evaluate treatment response. The inhomogeneity of the data suggests the need to address limitations related to these tools with the employment of new techniques and the potential for a complementary use of both PET/CT and MRI to refine the sensitivity and achieve the standards for minimal residual disease (MRD) evaluation.

Modern imaging techniques for monitoring patients with multiple myeloma

Bone disease is a serious problem for many patients, often causing pathological bone fractures. A spinal collapse is a condition that affects the quality of life. It is the most frequent feature of multiple myeloma (MM), used in establishing the diagnosis and the need to start treatment. Because of these complications, imaging plays a vital role in the diagnosis and workup of myeloma patients. For many years, conventional radiography has been considered the gold standard for detecting bone lesions. The main reasons are the wide availability, low cost, the relatively low radiation dose and the ability of this imaging method to cover the entire bone system. Because of its incapacity to evaluate the response to therapy, more sophisticated techniques such as whole-body low-dose computed tomography (WBLDCT), whole-body magnetic resonance imaging, and 18F-fluorodeoxyglucose-positron emission tomography/computed tomography (PET/CT) are used. In this review, some of the advantages, indications and applications of the three techniques in managing patients with MM will be discussed. The European Myeloma Network guidelines have recommended WBLDCT as the imaging modality of choice for the initial assessment of MM-related lytic bone lesions. Magnetic resonance imaging is the gold-standard imaging modality for the detection of bone marrow involvement. One of the modern imaging methods and PET/CT can provide valuable prognostic data and is the preferred technique for assessing response to therapy.

Spinal MRI-Based Radiomics Analysis to Predict Treatment Response in Multiple Myeloma

OBJECTIVE

The aim of this study was to explore the clinical utility of spinal magnetic resonance imaging-based radiomics to predict treatment response (TR) in patients with multiple myeloma (MM).

METHODS

A total of 123 MM patients (85 in the training cohort and 38 in the test cohort) with complete response (CR) (n = 40) or non-CR (n = 83) were retrospectively enrolled in the study. Key feature selection and data dimension reduction were performed using the least absolute shrinkage and selection operator regression. A nomogram was built by combining radiomic signatures and independent clinical risk factors. The prediction performance of the nomogram was assessed using the area under the receiver operating characteristic curve (AUC), calibration curves, and decision curve analysis. Treatment response was assessed by determining the serum and urinary levels of M-proteins, serum-free light chain ratio, and the percentage of bone marrow plasma cells.

RESULTS

Thirteen features were selected to build a radiomic signature. The International Staging System (ISS) stage was selected as an independent clinical factor. The radiomic signature and nomogram showed better calibration and higher discriminatory capacity (AUC of 0.929 and 0.917 for the radiomics and nomogram in the training cohort, respectively, and 0.862 and 0.874 for the radiomics and nomogram in the test cohort, respectively) than the clinical model (AUC of 0.661 and 0.674 in the training and test cohort, respectively). Decision curve analysis confirmed the clinical utility of the radiomics model.

CONCLUSIONS

Nomograms incorporating a magnetic resonance imaging-based radiomic signature and ISS stage help predict the response to chemotherapy for MM and can be useful in clinical decision-making.

18F-FDG-PET/CT in relapsed multiple myeloma: Are prognostic thresholds different from first-line therapy?

Purpose

While ¹⁸F-FDG PET/CT yields valuable prognostic information for patients in first-line therapy of multiple myeloma (MM), its prognostic relevance in relapse is not established. Available studies of relapsed MM describe prognostic thresholds for frequently used PET/CT parameters that are significantly higher than those identified in the first-line setting. The purpose of this study was to evaluate the prognostic role of PET/CT in relapsed MM, based on parameters used in the first-line setting.

Methods

Our retrospective study included 36 patients with MM who had received autologous or allogeneic stem cell transplantation, suffered at least one relapse, and underwent FDG-PET/CT at relapse. Number of focal bone lesions (FL), maximal standardised uptake value (SUVmax), and presence of PET-positive extramedullary lesions (EMD) were analysed.

Results

For the number of FLs, the prognostic value was demonstrated with a cut-off of > 3 (median OS 3.8 months vs. not reached, p = 0.003). Median OS of patients with SUVmax ≤ 4 was not reached, while it was 3.9 months in patients with SUVmax > 4 (p = 0.014). Presence of EMD was a significant prognostic parameter too, with median OS of 3.6 months versus not reached (p = 0.004). The above-mentioned parameters showed prognostic significance for PFS as well. Combination of higher ISS stage and PET/CT parameters identified patients with particularly short OS (3.7 months vs. not reached, p < 0.001) and PFS (3.6 vs. 11.7 months p < 0.001).

Conclusion

The PET/CT parameters SUVmax > 4, nFL > 3, and presence of EMD identify patients with poor prognosis not only in the first-line setting but also in relapsed MM.

Application of diffusion-weighted whole-body MRI for response monitoring in multiple myeloma after chemotherapy: a systematic review and meta-analysis

OBJECTIVE

Myeloma Response Assessment and Diagnosis System recently published provides a framework for the standardised interpretation of DW-WBMRI in response assessment of multiple myeloma (MM) based on expert opinion. However, there is a lack of meta-analysis providing higher-level evidence to support the recommendations. In addition, some disagreement exists in the literature regarding the effect of timing and lesion subtypes on apparent diffusion coefficient (ADC) value changes post-treatment.

METHOD

Medline, Cochrane and Embase were searched from inception to 20th July 2021, using terms reflecting multiple myeloma and DW-WBMRI. Using PRISMA reporting guidelines, data were extracted by two investigators. Quality was assessed by the Quality Assessment of Diagnostic Accuracy Studies-2 method.

RESULTS

Of the 74 papers screened, 10 studies were included comprising 259 patients (127 males and 102 females) and 1744 reported lesions. Responders showed a significant absolute ADC change of 0.21×10^-3 mm/s² (95% CI, 0.01-0.41) with little evidence of heterogeneity (Cochran Q, p = 0.12, I² = 45%) or publication bias (p = 0.737). Non-responders did not show a significant absolute difference in ADC (0.06 ×10^-3 mm/s², 95% CI, -0.07 to 0.19). A percentage ADC increase of 34.78% (95% CI, 10.75-58.81) was observed in responders. Meta-regression showed an inverse trend between ADC increases and time since chemotherapy initiation which did not reach statistical significance (R² = 20.46, p = 0.282).

CONCLUSIONS

This meta-analysis supports the use of the DW-WBMRI as an imaging biomarker for response assessment. More evidence is needed to further characterise ADC changes by lesion subtypes over time.

KEY POINTS

• In multiple myeloma patients who received chemotherapy, responders have a significant absolute increase in ADC values that is not seen in non-responders. • A 35% increase in ADC from baseline values is found to classify response post-induction chemotherapy which corroborates with expert opinion from the Myeloma Response Assessment and Diagnosis System. • More evidence is needed to further characterise ADC changes by lesion subtypes over time after induction of therapy.

Imaging of treatment response and minimal residual disease in multiple myeloma: state of the art WB-MRI and PET/CT

Bone imaging has been intimately associated with the diagnosis and staging of multiple myeloma (MM) for more than 5 decades, as the presence of bone lesions indicates advanced disease and dictates treatment initiation. The methods used have been evolving, and the historical radiographic skeletal survey has been replaced by whole body CT, whole body MRI (WB-MRI) and [¹⁸F]FDG-PET/CT for the detection of bone marrow lesions and less frequent extramedullary plasmacytomas.Beyond diagnosis, imaging methods are expected to provide the clinician with evaluation of the response to treatment. Imaging techniques are consistently challenged as treatments become more and more efficient, inducing profound response, with more subtle residual disease. WB-MRI and FDG-PET/CT are the methods of choice to address these challenges, being able to assess disease progression or response and to detect "minimal" residual disease, providing key prognostic information and guiding necessary change of treatment.This paper provides an up-to-date overview of the WB-MRI and PET/CT techniques, their observations in responsive and progressive disease and their role and limitations in capturing minimal residual disease. It reviews trials assessing these techniques for response evaluation, points out the limited comparisons between both methods and highlights their complementarity with most recent molecular methods (next-generation flow cytometry, next-generation sequencing) to detect minimal residual disease. It underlines the important role of PET/MRI technology as a research tool to compare the effectiveness and complementarity of both methods to address the key clinical questions.

Review of diffusion-weighted imaging and dynamic contrast-enhanced MRI for multiple myeloma and its precursors (monoclonal gammopathy of undetermined significance and smouldering myeloma)

The last decades, increasing research has been conducted on dynamic contrast-enhanced and diffusion-weighted MRI techniques in multiple myeloma and its precursors. Apart from anatomical sequences which are prone to interpretation errors due to anatomical variants, other pathologies and subjective evaluation of signal intensities, dynamic contrast-enhanced and diffusion-weighted MRI provide additional information on microenvironmental changes in bone marrow and are helpful in the diagnosis, staging and follow-up of plasma cell dyscrasias. Diffusion-weighted imaging provides information on diffusion (restriction) of water molecules in bone marrow and in malignant infiltration. Qualitative evaluation by visually assessing images with different diffusion sensitising gradients and quantitative evaluation of the apparent diffusion coefficient are studied extensively. Dynamic contrast-enhanced imaging provides information on bone marrow vascularisation, perfusion, capillary resistance, vascular permeability and interstitial space, which are systematically altered in different disease stages and can be evaluated in a qualitative and a (semi-)quantitative manner. Both diffusion restriction and abnormal dynamic contrast-enhanced MRI parameters are early biomarkers of malignancy or disease progression in focal lesions or in regions with diffuse abnormal signal intensities. The added value for both techniques lies in better detection and/or characterisation of abnormal bone marrow otherwise missed or misdiagnosed on anatomical MRI sequences. Increased detection rates of focal lesions or diffuse bone marrow infiltration upstage patients to higher disease stages, provide earlier access to therapy and slower disease progression and allow closer monitoring of high-risk patients. Despite promising results, variations in imaging protocols, scanner types and post-processing methods are large, thus hampering universal applicability and reproducibility of quantitative imaging parameters. The myeloma response assessment and diagnosis system and the international myeloma working group provide a systematic multicentre approach on imaging and propose which parameters to use in multiple myeloma and its precursors in an attempt to overcome the pitfalls of dynamic contrast-enhanced and diffusion-weighted imaging.Single sentence summary statementDiffusion-weighted imaging and dynamic contrast-enhanced MRI provide important additional information to standard anatomical MRI techniques for diagnosis, staging and follow-up of patients with plasma cell dyscrasias, although some precautions should be taken on standardisation of imaging protocols to improve reproducibility and application in multiple centres.

Diffuse vertebral marrow changes at MRI: Multiple myeloma or normal?

Five MRI patterns of marrow involvement (diffuse, focal, combined diffuse and focal, variegated, and normal) are observed in patients with a marrow proliferative disorder including MM. The wide range of marrow involvement patterns in monoclonal plasma cell proliferative disorders mirrors that of their natural histories that can vary from indolent to rapidly lethal. MRI of the axial bone marrow contributes to stage these disorders, but it should not be obtained for disease detection and characterization because of its limited specificity and sensitivity. At MRI, diffuse benign hematopoietic marrow hyperplasia and marrow heterogeneities in elderly patients mimic the diffuse and variegated patterns observed in MM patients. Careful analysis of fat- and fluid-sensitive MR images and quantitative marrow assessment by using MRI and FDG-PET can contribute in differentiating these changes from those associated with neoplastic marrow infiltration, with some residual overlapping findings.

In vivo quantitative assessment of therapeutic response to bortezomib therapy in disseminated animal models of multiple myeloma with [18F]FDG and [64Cu]Cu-LLP2A PET

Background

Multiple myeloma (MM) is a disease of cancerous plasma cells in the bone marrow. Imaging-based timely determination of therapeutic response is critical for improving outcomes in MM patients. Very late antigen-4 (VLA4, CD49d/CD29) is overexpressed in MM cells. Here, we evaluated [¹⁸F]FDG and VLA4 targeted [⁶⁴Cu]Cu-LLP2A for quantitative PET imaging in disseminated MM models of variable VLA4 expression, following bortezomib therapy.

Methods

In vitro and ex vivo VLA4 expression was evaluated by flow cytometry. Human MM cells, MM.1S-CG and U266-CG (C: luciferase and G: green fluorescent protein), were injected intravenously in NOD-SCID gamma mice. Tumor progression was monitored by bioluminescence imaging (BLI). Treatment group received bortezomib (1 mg/kg, twice/week) intraperitoneally. All cohorts (treated, untreated and no tumor) were longitudinally imaged with [¹⁸F]FDG (7.4–8.0 MBq) and [⁶⁴Cu]Cu-LLP2A (2–3 MBq; Molar Activity: 44.14 ± 1.40 MBq/nmol) PET, respectively.

Results

Flow cytometry confirmed high expression of CD49d in U266 cells (> 99%) and moderate expression in MM.1S cells (~ 52%). BLI showed decrease in total body flux in treated mice. In MM.1S-CG untreated versus treated mice, [⁶⁴Cu]Cu-LLP2A localized with a significantly higher SUV_mean in spine (0.58 versus 0.31, p < 0.01) and femur (0.72 versus 0.39, p < 0.05) at week 4 post-tumor inoculation. There was a four-fold higher uptake of [⁶⁴Cu]Cu-LLP2A (SUV_mean) in untreated U266-CG mice compared to treated mice at 3 weeks post-treatment. Compared to [⁶⁴Cu]Cu-LLP2A, [¹⁸F]FDG PET detected treatment-related changes at later time points.

Conclusion

[⁶⁴Cu]Cu-LLP2A is a promising tracer for timely in vivo assessment of therapeutic response in disseminated models of MM.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13550-021-00840-4.

Comparison of conventional magnetic resonance imaging and diffusion-weighted imaging in the differentiation of bone plasmacytoma from bone metastasis in the extremities

PURPOSE

To compare conventional magnetic resonance imaging (MRI) and diffusion-weighted imaging (DWI) in the differentiation of bone plasmacytoma from bone metastasis in the extremities.

MATERIALS AND METHODS

A total of 65 patients with 27 bone plasmacytomas (11 men; mean age, 63.6±8.2 [SD] years) and 38 patients with bone metastases (20 men; mean age, 64.1±11.5 [SD] years) were retrospectively included. Plasmacytomas and metastases were compared for size, peritumoral edema, signal intensity (SI), SI pattern, apparent diffusion coefficient (ADC) values and standard deviation (SD) of ADC. Receiver operating characteristic analysis with area under the curve (AUC) was used to calculate sensitivity, specificity, and accuracy of MRI and DWI for the diagnosis of plasmacytoma according to a defined cut-off value.

RESULTS

On conventional MRI, plasmacytomas showed less peritumoral edema (22% vs. 71%; P<0.001), were more often hyperintense on T1-weighted image (48% vs. 18%; P=0.022) and more homogeneous on T2-weighted image (78% vs. 26%; P<0.001) and contrast-enhanced T1-weighted images (70% vs. 25%; P=0.001) than bone metastases. Mean ADC value and SD of ADC were significantly lower in bone plasmacytomas (760.1±196.9 [SD] μm²/s and 161.5±62.7 [SD], respectively) than in bone metastases (1214.2±382.6 [SD] μm²/s and 277.0±110.3 [SD], respectively) (P<0.001). Using an ADC value≤908.3μm²/s, DWI yielded 88% sensitivity and 78% specificity for the diagnosis of plasmacytoma. ADC value yielded best area under the curve (AUC=0.913), followed by SD of ADC (AUC=0.814) and homogeneity on T2-weighted images (AUC=0.757). The combination of conventional MRI and DWI (AUC=0.894) showed improved diagnostic performance over conventional MRI alone (AUC= 0.843) for discriminating between plasmacytoma and metastasis.

CONCLUSION

Conventional MRI in combination with DWI can be useful to discriminate between bone plasmacytoma and bone metastasis in the extremities.

Pictorial review of whole body MRI in myeloma: emphasis on diffusion-weighted imaging

There have been major advances in myeloma imaging over the past few years with focal lesions on imaging now forming part of the disease defining criteria. Whole body diffusion-weighted MRI (WB-MRI) is considered the most sensitive technique for the detection of focal active lesions. This pictorial review will focus on imaging the spectrum of myelomatous disorders on WB-MRI including diffusion and Dixon sequences. The typical imaging patterns of disease are demonstrated including in the contexts of staging, presumed solitary plasmacytoma, smouldering myeloma and examples of paramedullary and extramedullary disease. The utility of diffusion-weighted imaging in response assessment is a major advantage and this will be exemplified here.

The Spectrum of Rib Neoplasms in Adults: A Practical Approach and Multimodal Imaging Review

OBJECTIVE. Adult neoplasms of the ribs are a heterogeneous group consisting of both benign and aggressive entities. Rib neoplasms have a variety of overlapping imaging features, with much of the imaging data disjointed across the musculoskeletal, thoracic, and oncologic imaging literature. Arrival at accurate diagnosis can therefore be quite challenging. This article consolidates this information and introduces the reader to an algorithmic approach to rib lesion evaluation based on imaging. CONCLUSION. Rib neoplasms are a diverse group of benign and malignant entities, which often makes determining an accurate diagnosis challenging. Evaluation requires a multipronged approach that incorporates radiographic imaging features, nonradiographic imaging findings, lesion location, and clinical data.

Multiple myeloma manifesting as an ocular salmon patch - a case report

Multiple myeloma (MM) is the second most prevalent hematologic malignancy after non-Hodgkin lymphoma and is currently considered incurable. Clinical ophthalmic manifestations of MM are rare but at the same time diverse. Ocular surface manifestations of multiple myeloma are uncommon. Conjunctival 'salmon patch' is a typical ocular surface ophthalmological sign with a distinct set of differential diagnoses, including most often ocular adnexal lymphoma. This case report presents a 33-year-old female with a relapse of MM manifesting as a conjunctival 'salmon patch'. The patient initially responded well to medical management including high dose melphalan supported by a third autologous stem cell transplantation (ASCT) and did not require further surgical excision of the ocular lesion. It is suggested that MM should be included in the differential diagnosis of 'salmon patch' conjunctival lesions.

Lack of Spleen Signal on Diffusion Weighted MRI is associated with High Tumor Burden and Poor Prognosis in Multiple Myeloma: A Link to Extramedullary Hematopoiesis?

Due to the low frequency of abnormalities affecting the spleen, this organ is often overlooked during radiological examinations. Here, we report on the unexpected finding, that the spleen signal on diffusion-weighted MRI (DW-MRI) is associated with clinical parameters in patients with plasma cell dyscrasias.

Methods: We investigated the spleen signal on DW-MRI together with clinical and molecular parameters in 295 transplant-eligible newly diagnosed Multiple Myeloma (NDMM) patients and in 72 cases with monoclonal gammopathy of undetermined significance (MGUS).

Results: Usually, the spleen is the abdominal organ with the highest intensities on DW-MRI. Yet, significant signal loss on DW-MRI images was seen in 71 of 295 (24%) NDMM patients. This phenomenon was associated with the level of bone marrow plasmacytosis (P=1x10^-10) and International Staging System 3 (P=0.0001) but not with gain(1q), and del(17p) or plasma cell gene signatures. The signal was preserved in 72 individuals with monoclonal gammopathy of undetermined significance and generally re-appeared in MM patients responding to treatment, suggesting that lack of signal reflects increased tumor burden. While absence of spleen signal in MM patients with high risk disease defined a subgroup with very poor outcome, re-appearance of the spleen signal after autologous stem cell transplantation was seen in patients with improved outcome. Our preliminary observation suggests that extramedullary hematopoiesis in the spleen is a factor that modifies the DW-MRI signal of this organ.

Conclusions: The DW-MRI spleen signal is a promising marker for tumor load and provides prognostic information in MM.

Typical aspects in the rehabilitation of cancer patients suffering from metastatic bone disease or multiple myeloma

Background

The aim of this study was to present a practical concept focusing on typical aspects of regular physical activity, exercise and physical modalities for patients suffering from metastatic bone disease or multiple myeloma.

Methods

A narrative review of the relevant scientific literature and presentation of clinical experiences.

Results

In cancer patients with metastatic bone disease or multiple myeloma, pain is treated in an interdisciplinary and multimodal setting by using medication, radiotherapy and physical medical modalities (e.g. transcutaneous electrical nerve stimulation); however, modalities increasing local blood flow, such as ultrasound therapy, thermotherapy, massage, various electrotherapy options, are not performed at the site of the tumor. For physical activity and exercise, a suitable indication of the static and dynamic capacity of the affected skeletal structures is essential. This process includes strategies to maintain and improve mobility and independence. Individually tailored and adapted physical activity and exercise concepts (programs) within a multidisciplinary and interdisciplinary setting (tumor board) are used to manage the condition and bone load-bearing capacity of the patient. Typical clinical features and complications, such as pathological fractures in patients suffering from metastatic bone disease and additionally hypercalcemia, monoclonal gammopathy with bone marrow aplasia and risk of renal failure in patients with multiple myeloma have to be considered when planning supportive strategies and rehabilitation.

Conclusion

In order to ensure the safety and effectiveness of regular physical activity, exercise, and physical modalities in patients with metastatic bone disease or multiple myeloma, typical contraindications and considerations should be noted.