Comparison of whole-body 64-slice multidetector computed tomography and conventional radiography in staging of multiple myeloma

Selenoprotein W engages in overactive osteoclast differentiation in multiple myeloma

BACKGROUND

Patients with multiple myeloma exhibit malignant osteolytic bone disease due to excessive osteoclast formation and function. We recently identified that osteoclastogenic stimulator selenoprotein W (SELENOW) is upregulated via ERK signaling and downregulated via p38 signaling during receptor activator of nuclear factor (NF)-κΒ ligand (RANKL)-induced osteoclast differentiation. In the intrinsic physiological process, RANKL-induced downregulation of SELENOW maintains proper osteoclast differentiation; in contrast, forced overexpression of SELENOW leads to overactive osteoclast formation and function.

METHODS AND RESULTS

We observed that SELENOW is highly expressed in multiple myeloma-derived peripheral blood mononuclear cells (PBMCs) and mature osteoclasts when compared to healthy controls. Also, the level of tumor necrosis factor alpha (TNFα), a pathological osteoclastogenic factor, is increased in the PBMCs and serum of patients with multiple myeloma. ERK activation by TNFα was more marked and sustained than that by RANKL, allowing SELENOW upregulation. Excessive expression of SELENOW in osteoclast progenitors and mature osteoclasts derived from multiple myeloma facilitated efficient nuclear translocation of osteoclastogenic transcription factors NF-κB and NFATc1, which are favorable for osteoclast formation.

CONCLUSION

Our findings suggest a possibility that feedforward signaling of osteoclastogenic SELENOW by TNFα derived from multiple myeloma induces overactive osteoclast differentiation, leading to bone loss during multiple myeloma.

Computed tomographic findings in dogs with multiple myeloma

BACKGROUND

Computed tomography (CT) is considered the first-line imaging modality for human patients with suspected multiple myeloma (MM). Recently the diagnostic criteria for human MM have been updated.

OBJECTIVES

To describe and provide a baseline of the CT features and distribution of osseous lesions in dogs diagnosed with MM and to describe the change of initial osseous lesions after the start of treatment in a subset of dogs.

METHODS

Single-centre, retrospective, descriptive, case series. Dogs were included when they met the updated MM criteria and if a staging CT was performed at the time of diagnosis and prior to initiation of treatment. When available, change of osseous lesions was assessed on serial imaging studies.

RESULTS

Thirteen dogs met the inclusion criteria. All dogs had involvement of the axial skeleton and 9/13 (69%) had concurrent involvement of the appendicular skeleton. Large (≥1 cm), lytic, 'punched out' or expansile bony lesions and regions of permeative lysis were most common and mainly affected the vertebral column. Discrete intramedullary soft tissue attenuating lesions of the proximal appendicular skeleton were observed in 8/13 dogs (61%) and bilateral involvement of both humeri and femurs was seen in 4/9 dogs (44%). A subset of dogs underwent serial imaging and progressive replacement of the contrast-enhancing lesions with fat attenuating tissue was observed for all dogs, corresponding with clinical improvement.

CONCLUSIONS

This case series provides a baseline knowledge of the initial and follow-up CT features in dogs diagnosed with MM based on updated criteria.

Whole body imaging in musculoskeletal oncology: when, why, and how

The use of whole-body imaging has become increasingly popular in oncology due to the possibility of evaluating total tumor burden with a single imaging study. This is particularly helpful in cases of widespread disease where dedicated regional imaging would make the evaluation more expensive, time consuming, and prone to more risks. Different techniques can be used, including whole-body MRI, whole-body CT, and PET-CT. Common indications include surveillance of cancer predisposing syndromes, evaluation of osseous metastases and clonal plasma cell disorders such as multiple myeloma, and evaluation of soft tissue lesions, including peripheral nerve sheath tumors. This review focuses on advanced whole-body imaging techniques and their main uses in musculoskeletal oncology.

Computed tomography with adjusted dose for body mass index may be superior to whole-body radiography especially in elderly patients with multiple myeloma

BACKGROUND

Whole-body skeletal radiography has traditionally been used in the management of multiple myeloma for defining treatment strategies. For several reasons, radiography has been replaced by computed tomography (CT) covering the same regions.

PURPOSE

To evaluate the body mass index (BMI) adjusted effective radiation dose from two different methods of whole-body radiologic imaging for multiple myeloma assessment.

MATERIAL AND METHODS

The current investigation analyses the dose to patients resulting from the two methods, conventional radiography supplemented with tomosynthesis (203 examinations) and CT (264 examinations). All patients subject to myeloma staging for 4.5 years were included in the study. Exposure parameters were collected from the PACS and conversion factors were calculated using the software packages PCXMC and VirtualDose enabling the calculation of the effective dose to each patient based on BMI. The Mann-Whitney U test was used for comparisons between groups.

RESULTS

Patients were subject to a median effective dose of 2.5 mSv for conventional radiography and 5.1 mSv for CT, a statistically significant difference.

CONCLUSION

The effective dose for whole-body CT in assessing multiple myeloma is twice as high as for whole-body skeletal survey with modern digital radiography, but at a low level and considerably less than the levels quoted in the earlier studies of ∼30 mSv when the technique was first explored.

Newly Diagnosed Multiple Myeloma Patients with Skeletal-Related Events and Abnormal MRI Pattern Have Poor Survival Outcomes: A Prospective Study on 370 Patients

Contemporary information is sparse on the frequency of skeletal-related events (SREs) in multiple myeloma (MM) patients at a population-based level in the era of novel agents. In this context, we conducted this single-center, prospective, observational study to determine the incidence of SREs among newly diagnosed MMs (NDMM) and to explore the possible correlations with disease characteristics, imaging finding, and patient prognosis. A total of 370 patients with available baseline MRIs were included. Among them, 208 (56%) presented with at least one SRE at diagnosis. Fractures were the most common reported SREs (48%). The incidence of SREs at diagnosis was higher in patients with osteolytic lesions, abnormal MRI pattern, hypercalcemia, and at least 60% bone marrow infiltration by plasma cells. Importantly, the patients with normal MRI pattern, who did not present with SREs at diagnosis, had statistically significant improved median OS in comparison with the patients who had abnormal MRI patterns and/or the presence of SREs at diagnosis (9.3 vs. 6.6 years, p = 0.048). Our data, which represent one of a few systematic reports on the incidence and characteristics of SREs in the era of novel agents, was indicative of a high incidence of SREs at the time of MM diagnosis. Early detection of myeloma bone disease and tailored patient management are essential to optimize patient outcomes.

A prospective study of Skeletal survey versus Low-dose whole-body CT for Osteolytic lesions in Multiple Myeloma

Whole-body low-dose CT (WBLDCT) is recommended over classical skeletal surveys (CSS) for investigating bone disease in multiple myeloma (MM) based on retrospective studies. No prospective studies with serial follow-up scans exist.

OBJECTIVE

To compare WBLDCT to CSS for identifying progressive bone disease in MM in a prospective setting.

METHODS

Ninety-six patients with MM at Odense University Hospital and Stavanger Hospital were followed for up to four years. Patients were scanned with WBLDCT and CSS every year for the first two years and every six months thereafter or at suspicion of progression.

RESULTS

Nineteen cases of progressive bone disease were found using WBLDCT vs eight cases using CSS (p < 0.001). All cases of progressive bone disease using CSS were also identified by WBLDCT. Progression not found by CSS was primarily in the spine, sternum, and pelvis. Of the 19 cases, five patients had progressive bone disease only without other criteria for clinical progression. WBLDCT consistently identified more bone lesions per patient, 8.2 CI(6.8;9.6) vs CSS, 3.6 CI(2.7;4.5).

CONCLUSION

WBLDCT outperformed CSS for finding progressive bone disease and osteolytic lesions. More new lesions were found during follow-up by WBLDCT than CSS. Using CSS for lytic lesions will underestimate progression rates. Our data offer prospective evidence for the current recommendation using WBLDCT for skeletal evaluations in patients with multiple myeloma.

Diagnostic performance of computed tomography and diffusion-weighted imaging as first-line imaging modality according to the International Myeloma Working Group (IMWG) imaging algorithm for monoclonal plasma cell disorders

BACKGROUND

The latest International Myeloma Working Group (IMWG) guideline recommends low-dose whole-body (WB) computed tomography (CT) as the first-line imaging technique for the initial diagnosis of plasma cell disorders.

PURPOSE

To evaluate diagnostic performances of CT and diffusion-weighted imaging (DWI) as the first-line imaging modalities and assess misclassification rates obtained following the guideline.

MATERIAL AND METHODS

Two independent radiologists analyzed CT (acquired as PET/CT) and DWI (3-T; b-values = 50 and 900 s/mm²) of patients newly diagnosed with plasma cell disorder, categorizing the number of bone lesions. Diagnostic performance of CT and DWI was compared using the McNemar test, and misclassification rates were calculated with a consensus WB-MRI reading as the reference standard. Differences in lesion number categories were assessed using marginal homogeneity and kappa statistics.

RESULTS

Of 56 patients (36 men; mean age = 63.5 years), 39 had myeloma lesions. DWI showed slightly higher sensitivity for detecting myeloma lesions (97.4%) than CT (84.6%-92.3%; P > 0.05). CT showed significantly higher specificity (88.2%) than DWI (52.9%-58.8%; P<0.05). CT had a higher additional study requirement rate than DWI (7.7%-15.4% vs. 2.6%), but a lower unnecessary treatment rate (11.8% vs. 41.2%-47.1%). Both readers showed significant differences in categorization of the number of lesions on CT compared with the reference standard (P < 0.001), and one reader showed a significant difference on DWI (P = 0.006 and 0.098).

CONCLUSION

CT interpreted according to the IMWG guideline is a diagnostically effective first-line modality with relatively high sensitivity and specificity. DWI alone may not be an acceptable first-line imaging modality because of low specificity.

Detecting Multiple Myeloma Infiltration of the Bone Marrow on CT Scans in Patients with Osteopenia: Feasibility of Radiomics Analysis

It is difficult to detect multiple myeloma (MM) infiltration of the bone marrow on computed tomography (CT) scans of patients with osteopenia. Our aim is to determine the feasibility of using radiomics analysis to detect MM infiltration of the bone marrow on CT scans of patients with osteopenia. The contrast-enhanced thoracic CT scans of 104 patients with MM and 104 age- and sex-matched controls were retrospectively evaluated. All individuals had decreased bone density on radiography. The study group was divided into development (n = 160) and temporal validation sets (n = 48). The radiomics model was developed using 805 texture features extracted from the bone marrow for a development set, using a Random Forest algorithm. The developed models were applied to evaluate a temporal validation set. For comparison, three radiologists evaluated the CTs for the possibility of MM infiltration in the bone marrow. The diagnostic performances were assessed and compared using an area under the receiver operating characteristic curve (AUC) analysis. The AUC of the radiomics model was not significantly different from those of the radiologists (p = 0.056–0.821). The radiomics analysis results showed potential for detecting MM infiltration in the bone marrow on CT scans of patients with osteopenia.

Radiation exposure and establishment of diagnostic reference levels of whole-body low-dose CT for the assessment of multiple myeloma with second- and third-generation dual-source CT

BACKGROUND

In the assessment of diseases causing skeletal lesions such as multiple myeloma (MM), whole-body low-dose computed tomography (WBLDCT) is a sensitive diagnostic imaging modality, which has the potential to replace the conventional radiographic survey.

PURPOSE

To optimize radiation protection and examine radiation exposure, and effective and organ doses of WBLDCT using different modern dual-source CT (DSCT) devices, and to establish local diagnostic reference levels (DRL).

MATERIAL AND METHODS

In this retrospective study, 281 WBLDCT scans of 232 patients performed between January 2017 and April 2020 either on a second- (A) or third-generation (B) DSCT device could be included. Radiation exposure indices and organ and effective doses were calculated using a commercially available automated dose-tracking software based on Monte-Carlo simulation techniques.

RESULTS

The radiation exposure indices and effective doses were distributed as follows (median, interquartile range): (A) second-generation DSCT: volume-weighted CT dose index (CTDI_vol) 1.78 mGy (1.47-2.17 mGy); dose length product (DLP) 282.8 mGy·cm (224.6-319.4 mGy·cm), effective dose (ED) 1.87 mSv (1.61-2.17 mSv) and (B) third-generation DSCT: CTDI_vol 0.56 mGy (0.47-0.67 mGy), DLP 92.0 mGy·cm (73.7-107.6 mGy·cm), ED 0.61 mSv (0.52-0.69 mSv). Radiation exposure indices and effective and organ doses were significantly lower with third-generation DSCT (P < 0.001). Local DRLs could be set for CTDI_vol at 0.75 mGy and DLP at 120 mGy·cm.

CONCLUSION

Third-generation DSCT requires significantly lower radiation dose for WBLDCT than second-generation DSCT and has an effective dose below reported doses for radiographic skeletal surveys. To ensure radiation protection, DRLs regarding WBLDCT are required, where our locally determined values may help as benchmarks.

Ultra-Low-Dose Whole-Body Computed Tomography Protocol Optimization for Patients With Plasma Cell Disorders: Diagnostic Accuracy and Effective Dose Analysis From a Reference Center

BACKGROUND

The whole-body low-dose CT (WBLDCT) is the first-choice imaging technique in patients with suspected plasma cell disorder to assess the presence of osteolytic lesions. We investigated the performances of an optimized protocol, evaluating diagnostic accuracy and effective patient dose reduction using a latest generation scanner.

METHODS AND MATERIALS

Retrospective study on 212 patients with plasma cell disorders performed on a 256-row CT scanner. First, WBLDCT examinations were performed using a reference protocol with acquisition parameters obtained from literature. A phantom study was performed for protocol optimization for subsequent exams to minimize dose while maintaining optimal diagnostic accuracy. Images were analyzed by three readers to evaluate image quality and to detect lesions. Effective doses (E) were evaluated for each patient considering the patient dimensions and the tube current modulation.

RESULTS

A similar, very good image quality was observed for both protocols by all readers with a good agreement at repeated measures ANOVA test (p>0.05). An excellent inter-rater agreement for lesion detection was achieved obtaining high values of Fleiss' kappa for all the districts considered (p<0.001). The optimized protocol resulted in a 56% reduction of median DLP (151) mGycm, interquartile range (IQR) 128-188 mGycm vs. 345 mGycm, IQR 302-408 mGycm), of 60% of CTDIvol (2.2 mGy, IQR 1.9-2.7 mGy vs. 0.9 mGy, IQR 0.8-1.2 mGy). The median E value was about 2.6 mSv (IQR 1.7-3.5 mSv) for standard protocol and about 1.5 mSv (IQR 1.4-1.7 mSv) for the optimized one. Dose reduction was statistically significant with p<0.001.

CONCLUSIONS

Protocol optimization makes ultra-low-dose WBLDCT feasible on latest generation CT scanners for patients with plasma cell disorders with effective doses inferior to conventional skeletal survey while maintaining excellent image quality and diagnostic accuracy. Dose reduction is crucial in such patients, as they are likely to undergo multiple whole-body CT scans during follow-up.

Systemic Mastocytosis: Radiological Point of View

Radiological diagnosis of systemic mastocytosis (SM) can be hard to establish. This difficulty is mainly due to the variable radiological features involving many organ systems (e.g., respiratory, cardiovascular, lympho-reticular, digestive systems, and most commonly skin), and above all, to the broad spectrum of skeletal findings. Skeletal involvement is the most common and prominent imaging feature in patients with SM and represents a prognostic factor as it may entail an aggressive course of the disease. Diagnosis, largely established by histological evaluation of a bone marrow trephine biopsy, supplemented by imaging modalities such as radiography, CT, and magnetic resonance imaging, requires a team approach between the hematologist, radiologist, and pathologist. The general radiologist needs to be familiar with the imaging findings because they may be the first to suggest the correct diagnosis. The primary purpose of this review article was to equip clinicians with pertinent radiological semiotics by presenting relevant radiological features that assist early diagnosis and selection of an effective treatment.

Diagnostic Value of Whole-Body MRI Short Protocols in Bone Lesion Detection in Multiple Myeloma Patients

The aim of the study is to evaluate the effectiveness of short whole-body magnetic resonance imaging (WBMRI) protocols for the overall assessment of bone marrow involvement in patients with multiple myeloma (MM), in comparison with standard whole-body MRI protocol. Patients with biopsy-proven MM, who underwent a WBMRI with full-body coverage (from vertex to feet) were retrospectively enrolled. WBMRI images were independently evaluated by two expert radiologists, in terms of infiltration patterns (normal, focal, diffuse, and combined), according to location (the whole skeleton was divided into six anatomic districts: skull, spine, sternum and ribs, upper limbs, pelvis and proximal two-thirds of the femur, remaining parts of lower limbs) and lytic lesions number (<5, 5-20, and >20). The majority of patients showed focal and combined infiltration patterns with bone lesions predominantly distributed in the spine and pelvis. As skull and lower limbs are less frequently involved by focal bone lesions, excluding them from the standard MRI protocol allows to obtain a shorter protocol, maintaining a good diagnostic value.

Whole Body Low Dose Computed Tomography (WBLDCT) Can Be Comparable to Whole-Body Magnetic Resonance Imaging (WBMRI) in the Assessment of Multiple Myeloma

Aim of the study is to compare the agreement between whole-body low-dose computed tomography (WBLDCT) and magnetic resonance imaging (WBMRI) in the evaluation of bone marrow involvement in patients with multiple myeloma (MM). Patients with biopsy-proven MM, who underwent both WBLDCT and WBMRI were retrospectively enrolled. After identifying the presence of focal bone involvement (focal infiltration pattern), the whole skeleton was divided into five anatomic districts (skull, spine, sternum and ribs, pelvis, and limbs). Patients were grouped according to the number and location of the lytic lesions (<5, 5-20, and >20) and Durie and Salmon staging system. The agreement between CT and MRI regarding focal pattern, staging, lesion number, and distribution was assessed using the Cohen Kappa statistics. The majority of patients showed focal involvement. According to the distribution of the focal lesions and Durie Salmon staging, the agreement between CT and MRI was substantial or almost perfect (all κ > 0.60). The agreement increased proportionally with the number of lesions in the pelvis and spine (κ = 0.373 to κ = 0.564, and κ = 0.469-0.624), while for the skull the agreement proportionally decreased without reaching a statistically significant difference (p > 0.05). In conclusion, WBLDCT showed an almost perfect agreement in the evaluation of focal involvement, staging, lesion number, and distribution of bone involvement in comparison with WBMRI.

Whole-body low-dose computed tomography (WBLDCT) in staging and re-staging of multiple myeloma

The objective of this study is to evaluate the prognostic features of multiple myeloma (MM) using whole-body low-dose computed tomography (WBLDCT). One hundred three patients with biopsy-proven MM who underwent WBLDCT were retrospectively enrolled. The evolution of osteolytic lesions overtime was performed by measuring the maximum axial diameter at the baseline (T₀) and the end of follow-up (T_e), by using a cut-off value of 10 mm. The location and dimension of up to three lesions were registered. The time-to-fracture (TTF) was recorded. Sixty-three percent of patients presented a focal pattern, 22% a diffuse pattern, and 15% a combined one. Seventy-two percent of patients with lesions ≤ 10 mm presented stability, 27% a dimensional increase, and 1% a decrease. Patients with lesions >10 mm showed a statistically significant difference regarding the mean difference of axial diameter between T₀ and T_e (p = 0.015). Patients with lesions >10 mm showed an odds ratio (OR) of 29.8 (95%CIs 3.8-230.5) to develop at least one fracture. Mean TTF was significantly lower in patients with lesions >10 mm in comparison with lesions ≤ 10 mm (9 ± 3 vs 23 ± 7 months, respectively, p = 0.011). WBLDCT represents a reliable imaging-based tool for proper management of MM patients, showing that diffuse form or small lytic lesions may deserve a less frequent follow-up.

Whole-Body Low-Dose CT in Multiple Myeloma: Diagnostic Value of Appendicular Medullary Patterns of Attenuation

OBJECTIVE. The purpose of this article is to analyze whole-body low-dose CT-detected appendicular medullary patterns of attenuation in patients with newly diagnosed multiple myeloma and to determine the diagnostic performance of whole-body low-dose CT in detecting diffuse marrow infiltration. MATERIALS AND METHODS. A total of 76 patients with myeloma who underwent whole-body low-dose CT and spinal MRI at initial assessment were retrospectively analyzed. The medullary cavities of femurs and humeri were evaluated qualitatively and quantitatively on CT. Medullary attenuation and SD-to-mean attenuation ratio were recorded for each long bone. The pattern of marrow involvement on spinal MRI was used as reference. The chi-square test was used to evaluate the relationship between the CT-based appendicular medullary cavity pattern and the MRI pattern, and ROC analysis was performed to assess the diagnostic accuracy of CT attenuation measurements for the differentiation between diffuse and mixed CT-based appendicular medullary cavity patterns. RESULTS. Medullary attenuation differed significantly among mixed, nodular, and diffuse CT-based appendicular medullary cavity patterns in the femurs (mean, 34.23 HU and range, 15-61 HU; mean, 66.26 HU and range, 26-104 HU; mean, 92.80 HU and range, 53-127 HU, respectively) and humeri (mean, 22.18 HU and range, 9-41; mean, 61.18 HU and range, 23-93 HU; mean, 77.50 and range, 25-105 HU, respectively). To discriminate between diffuse and mixed CT-based appendicular medullary cavity patterns, optimal cutoff attenuation values were 63 HU (sensitivity, 97.7%; specificity, 100.0%) for the femurs, and 52 HU (sensitivity, 97.4%; specificity, 100.0%) for the humeri. A total of 24 of 30 (80.0%) patients with a diffuse MRI pattern showed a diffuse CT-based appendicular medullary cavity pattern on whole-body low-dose CT, and all patients with a diffuse CT-based appendicular medullary cavity pattern also showed a diffuse pattern on MRI. CONCLUSION. According to analysis of peripheral medullary patterns of attenuation, whole-body low-dose CT can identify patients with multiple myeloma with diffuse marrow involvement.

Whole Body Low Dose Computed Tomography Using Third-Generation Dual-Source Multidetector With Spectral Shaping: Protocol Optimization and Literature Review

For decades, the main imaging tool for multiple myeloma (MM) patient's management has been the conventional skeleton survey. In 2014 international myeloma working group defined the advantages of the whole-body low dose computed tomography (WBLDCT) as a gold standard, among imaging modalities, for bone disease assessment and subsequently implemented this technique in the MM diagnostic workflow. The aim of this study is to investigate, in a group of 30 patients with a new diagnosis of MM, the radiation dose (CT dose index, dose-length product, effective dose), the subjective image quality score and osseous/extra-osseous findings rate with a modified WBLDCT protocol. Spectral shaping and third-generation dual-source multidetector CT scanner was used for the assessment of osteolytic lesions due to MM, and the dose exposure was compared with the literature findings reported until 2020. Mean radiation dose parameters were reported as follows: CT dose index 0.3 ± 0.1 mGy, Dose-Length Product 52.0 ± 22.5 mGy*cm, effective dose 0.44 ± 0.19 mSv. Subjective image quality was good/excellent in all subjects. 11/30 patients showed osteolytic lesions, with a percentage of extra-osseous findings detected in 9/30 patients. Our data confirmed the advantages of WBLDCT in the diagnosis of patients with MM, reporting an effective dose for our protocol as the lowest among previous literature findings.

Multiple Myeloma, Version 3.2021, NCCN Clinical Practice Guidelines in Oncology

Multiple myeloma is a malignant neoplasm of plasma cells that accumulate in bone marrow, leading to bone destruction and marrow failure. This manuscript discusses the management of patients with solitary plasmacytoma, smoldering multiple myeloma, and newly diagnosed multiple myeloma.

Systemic mastocytosis revisited with an emphasis on skeletal manifestations

Systemic mastocytosis (SM) is a rare form of mastocytosis that can affect various organ systems. Bone involvement is the most common and prominent imaging feature in patients with SM regardless of the subtype. Furthermore, bone involvement is a prognostic factor as it may entail an aggressive course of the disease. Diagnosis is established by bone marrow biopsy complemented by imaging modalities such as radiography, CT, and magnetic resonance (MR) imaging. The radiographic and CT appearances are that of sclerotic, lytic, or mixed patterns with focal or diffuse distribution, involving primarily the axial skeleton and the ends of the long bones. Bone marrow infiltration is best recognized on MR imaging. Osteoporosis is common in SM; thus, a bone mineral density measurement at lumbar spine and proximal femur by dual-energy X-ray absorptiometry should be obtained. Imaging plays a huge part in the diagnostic process; when skeletal imaging findings are carefully interpreted and correlated with clinical features, they can lead to the suspicion of SM. The primary aims of this review article were to focus on the role of imaging in detection and characterization of skeletal patterns of SM and to discuss relevant clinical features that could facilitate prompt and correct diagnosis.

The Role of Low Dose Whole Body CT in the Detection of Progression of Patients with Smoldering Multiple Myeloma

Multiple myeloma (MM) is the second most common hematological malignancy, characterized by plasma cell bone marrow infiltration and end-organ involvement. Smoldering MM (SMM) is an intermediate clinical entity between MGUS and MM, with a risk of progression to symptomatic disease 10% per year. Bone disease is the most frequent symptom of MM, with ~90% of patients developing bone lesions throughout their disease course. Therefore, imaging plays a crucial role in diagnosis and management. Whole-body low-dose CT (WBLDCT) is widely available and has been incorporated in the latest diagnostic criteria of the IMWG. The purpose of this study was to evaluate the role of WBLDCT in the early identification of lesions in patients with SMM who progress solely with bone disease. In total, 100 asymptomatic patients were consecutively assessed with WBLDCT from July 2013 until March 2020 at baseline, 1-year after diagnosis and every 1 year thereafter. Ten percent of patients were identified as progressors with this single imaging modality. This is the first study to evaluate prospectively patients with SMM at different time points to identify early bone lesions related to MM evolution. Serial WBLDCT studies can identify early myeloma evolution and optimize disease monitoring and therapeutic strategies.

Diagnostic performance of 18 F-FDG-PET/CT compared to standard skeletal survey for detecting bone destruction in smouldering multiple myeloma: time to move forward

Skeletal survey (SS) continues to be used in the community to detect bone disease in patients with multiple myeloma (MM). While the false-negative rate is high, the specificity of SS is less well characterised. Here, we compare the diagnostic accuracy of SS compared to ¹⁸ F-FDG-PET/CT (positron emission tomography/computed tomography) in 79 patients referred to our tertiary centre with a diagnosis of smouldering MM. SS had a specificity of 83·1% (95% confidence interval: 72·0-90·5%). This study reinforces the importance of using more specific imaging techniques to avoid inaccurate diagnosis that could lead to the risks associated with unnecessary therapy in patients with smouldering MM.

Multiple Myeloma: Role of Imaging in Diagnosis, Staging, and Treatment Response Assessment

Multiple myeloma is a common hematologic malignancy of plasma cells. Differentiating multiple myeloma from the precursor stages of monoclonal gammopathy of undetermined significance and smoldering multiple myeloma is very important because the treatment approach is different for each. The diagnosis is mainly clinical, while the role of imaging is confined to the staging process, assessing response to therapy, and monitoring for disease progression. In this article, we examine the role of different imaging modalities in patients with multiple myeloma.

Imaging of Monoclonal Gammapathy of Undetermined Significance and Smoldering Multiple Myeloma

Multiple myeloma (MM) is always preceded by an initial monoclonal gammopathy of undetermined significance (MGUS) that then develops into asymptomatic or smoldering multiple myeloma (SMM), which constitutes an intermediate clinical stage between MGUS and MM. According to a recent study, risk factors for faster MGUS to MM progression include an M protein of 1.5 g/dL or more and an abnormal free light chain ratio in patients with non-IgM MGUS. Therefore, the International Myeloma Working Group (IMWG) decided to recommend whole-body computed tomography (WBCT) for patients with high-risk MGUS in order to exclude early bone destruction. Studies evaluating magnetic resonance imaging (MRI) in SMM found an optimal cutoff of two or more focal lesions to be of prognostic significance for fast progression into symptomatic disease and considered this biomarker as a myeloma-defining event (MDE) needing to start therapy with the aim to avoid progression to harmful bone lesions. Moreover, studies assessing positron emission tomography (PET) with computed tomography (CT) using 18F-deoxyglucose (FDG) (FDG-PET/CT) in SMM showed that presence of focal bone lesion without underlying osteolysis is associated with a rapid progression to symptomatic MM. Latest IMWG guidelines recommended to perform WBCT (either CT alone or as part of an FDG-PET/CT protocol) as the first imaging technique at suspected SMM and, if these images are negative or inconclusive, to perform whole-body MRI. The goal of this paper is to clarify the role of different imaging modalities in MGUS and SMM workups.

Organ dose and total effective dose of whole-body CT in multiple myeloma patients

OBJECTIVE

To evaluate organ dose and total effective dose of whole-body low-dose CT (WBLDCT) performed on different CT-scanner models in patients with multiple myeloma (MM) and to compare it to the effective dose of radiographic skeletal survey and representative diagnostic CTs.

MATERIAL AND METHODS

We retrospectively analyzed data from 228 patients (47.4% females, mean age 67.9 ± 10.4 years, mean weight 81.8 ± 22.4 kg) who underwent WBLDCT for the work-up or surveillance of MM. Patients were scanned using one of six multi-detector CT-scanners. Organ doses and total effective doses per scan were calculated using a commercially available dose-management platform (Radimetrics, Bayer Healthcare, Leverkusen, Germany). The median effective dose was compared to radiographic skeletal survey and representative diagnostic CTs.

RESULTS

The mean effective dose of our WBLDCT-protocol was 4.82 mSv. A significantly higher effective dose was observed in females compared to males (4.95 vs. 4.70 mSv, P = 0.002). Mean organ dose ranged from 3.72 mSv (esophagus) to 13.09 mSv (skeleton). Mean effective dose varied amongst different CT-scanners (range 4.34-8.37 mSv). The median effective dose of WBLDCT was more than twice the dose of a skeletal survey (4.82 vs. 2.04 mSv), 23% higher than a diagnostic contrast-enhanced chest CT (3.9 mSv), 46% lower than a diagnostic contrast-enhanced abdomen/pelvis CT (9.0 mSv), and 45% lower than a lumbar spine CT (8.7 mSv).

CONCLUSIONS

WBLDCT in MM has a higher effective dose than a radiographic skeletal survey, but a lower effective dose than diagnostic CTs of lumbar spine, abdomen and pelvis. This underlines the broad applicability of WBLDCT in the management of MM patients.

Value of low-dose whole-body CT in the management of patients with multiple myeloma and precursor states

OBJECTIVE

To determine the value of low-dose whole-body CT (WBCT) in the management of patients with multiple myeloma (MM) and precursor states.

MATERIALS AND METHODS

The study group comprised 116 patients (mean age: 68 ± 11 years, 48% women) who underwent WBCT for the work-up or surveillance of MM or MM precursor disease. WBCTs were reviewed for the presence of MM-related bone disease and incidental findings requiring therapy. The medical records, results from bone marrow aspirations and biopsies and follow-up imaging studies were reviewed to assess the influence of WBCT on patient management.

RESULTS

Whole-body CT led to a change in management in 32 patients (28%). Of those, 17 patients with MM precursor disease were found to have MM-related bone disease, 13 patients had progression of MM, requiring a change in treatment, in one patient hepatocellular carcinoma was diagnosed, requiring a change in therapy, and one patient had a rib lesion requiring intervention. In 65 patients (56%), WBCT was performed for surveillance of MM precursor disease or stable treated MM, and did not detect new lesions, thereby providing reassurance to the hematologist on disease status and management. In 15 patients (13%) WBCT was performed as a new baseline before a change or new therapy. In 4 patients (3%), WBCT was performed for a change in symptoms, but did not detect lesions that would lead to a change in management.

CONCLUSION

Whole-body CT provides important information for disease monitoring and detection of incidental findings, thereby improving the management of patients with MM.

Imaging in myeloma with focus on advanced imaging techniques

In recent years, there have been major advances in the imaging of myeloma with whole body MRI incorporating diffusion-weighted imaging, emerging as the most sensitive modality. Imaging is now a key component in the work-up of patients with a suspected diagnosis of myeloma. The International Myeloma Working Group now specifies that more than one focal lesion on MRI or lytic lesion on whole body low-dose CT or fludeoxyglucose (FDG) PET/CT fulfil the criteria for bone damage requiring therapy. The recent National Institute for Health and Care Excellence myeloma guidelines recommend imaging in all patients with suspected myeloma. In addition, there is emerging data supporting the use of functional imaging techniques (WB-DW MRI and FDG PET/CT) to predict outcome and evaluate response to therapy. This review summarises the imaging modalities used in myeloma, the latest guidelines relevant to imaging and future directions.

Imaging in multiple myeloma: How? When?

Bone disease is the most frequent feature of multiple myeloma (MM) and represents a marker of end-organ damage; it is used to establish the diagnosis and to dictate the immediate need for therapy. For this reason, imaging plays a significant role in the management of MM patients. Although conventional radiography has traditionally been the standard imaging modality, its low sensitivity in detecting osteolytic lesions and inability to evaluate response to therapy has called for the use of 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). In this review, the advantages, indications of use, and applications of the 3 techniques in the management of patients with MM in different settings will be discussed. The European Myeloma Network and the European Society for Medical Oncology 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 detection of bone marrow involvement, whereas PET/CT provides valuable prognostic data and is the preferred technique for assessment of response to therapy. Standardization of most of the techniques is ongoing.

How We Manage Patients with Plasmacytomas

PURPOSE OF REVIEW

To discuss the diagnostic approach, treatment options, and future considerations in the management of plasmacytomas, either solitary or in the context of overt multiple myeloma (MM).

RECENT FINDINGS

Advanced imaging techniques such as whole-body magnetic resonance imaging and positron emission tomography/computerized tomography are essential for the diagnostic workup of solitary plasmacytomas (SP) to rule out the presence of other disease foci. The role of flow cytometry and clonal plasma cell detection is currently under study together with other prognostic factors for the identification of patients with SP at high risk of progression to overt MM. Solitary plasmacytomas are treated effectively with local radiotherapy whereas systemic therapy is required at relapse. Clonal plasma cells that accumulate at extramedullary sites have distinct biological characteristics. Patients with MM and soft tissue involvement have poor outcomes and should be treated as ultra-high risk. A revised definition of SP that distinguishes between true solitary clonal PC accumulations and SP with minimal bone marrow involvement should be considered to guide an appropriate therapeutic and follow-up approach. Future studies should be conducted to determine optimum treatment approaches for patients with MM and paraskeletal or extramedullary disease.

Managing the cervical spine in multiple myeloma patients

Discuss the relevant literature on surgical and nonsurgical treatments for multiple myeloma (MM) and their complementary effects on overall treatment. Existing surgical algorithms designed for neoplasia of the spine may not suit the management of spinal myeloma. Less than a fifth of metastatic, including myelomatous lesions, occur in the cervical spine but have a poorer prognosis and surgery in this area carries a higher morbidity. With the advances of chemotherapy, early access to radiotherapy, early orthosis management, and high definition imaging, including CT and MRI, surgical indications in MM have changed. Medical decompression (or oncolysis), including in the presence of neurological deficit and orthotic stabilization, are proving viable nonsurgical options to manage MM. A key to decision making is the assessment and monitoring of biomechanical spinal stability as part of a multidisciplinary approach.

Recommendations for acquisition, interpretation and reporting of whole body low dose CT in patients with multiple myeloma and other plasma cell disorders: a report of the IMWG Bone Working Group

Whole Body Low Dose CT (WBLDCT) has important advantages as a first-line imaging modality for bone disease assessment in patients with plasma cell disorders and has been included in the 2014 International Myeloma Working Group (IMWG) criteria for multiple myeloma (MM) definition. Nevertheless, standardization guidelines for the optimal use of WBLDCT in MM patients are still lacking, preventing its more widespread use, both in daily practice and clinical trials. The aim of this report by the Bone Group of the IMWG is to provide practical recommendations for the acquisition, interpretation and reporting of WBLDCT in patients with multiple myeloma and other plasma cell disorders.

Comparison of whole body magnetic resonance imaging (WBMRI) to whole body computed tomography (WBCT) or 18F-fluorodeoxyglucose positron emission tomography/CT (18F-FDG PET/CT) in patients with myeloma: Systematic review of diagnostic performance

OBJECTIVES

To undertake a systematic review to determine the diagnostic performance of whole body MRI (WBMRI) including diffusion weighted sequences (DWI) compared to whole body computed tomography (WBCT) or 18F-fluorodeoxyglucose positron emission tomography/CT (18F-FDG PET/CT) in patients with myeloma.

METHODS

Two researchers searched the primary literature independently for WBMRI studies of myeloma. Data were extracted focusing on the diagnostic ability of WBMRI versus WBCT and 18F-FDG PET/CT. Meta-analysis was intended.

RESULTS

6 of 2857 articles were eligible that included 147 patients, published from 2008 to 2016. Studies were heterogeneous including both newly diagnosed & relapsed patients. All were single centre studies. Four of the six studies (66.7%) accrued prospectively and 5/6 (83.3%, 3 prospective) included WBMRI and 18F-FDG PET/CT. Three of seven (42.9%) included DWI. The lack of an independent reference standard for individual lesions was noted in 5/6 (83.3%) studies. Studies reported that WBMRI detected more lesions than 18F-FDG PET/CT (sensitivity 68-100% versus 47-100%) but was less specific (specificity 37-83% versus 62-85.7%). No paper assessed impact on management.

CONCLUSIONS

Studies were heterogeneous, the majority lacking an independent reference standard. Future prospective trials should address these limitations and assess the impact of WBMRI on management.

Diagnosis, treatment, and response assessment in solitary plasmacytoma: updated recommendations from a European Expert Panel

Solitary plasmacytoma is an infrequent form of plasma cell dyscrasia that presents as a single mass of monoclonal plasma cells, located either extramedullary or intraosseous. In some patients, a bone marrow aspiration can detect a low monoclonal plasma cell infiltration which indicates a high risk of early progression to an overt myeloma disease. Before treatment initiation, whole body positron emission tomography-computed tomography or magnetic resonance imaging should be performed to exclude the presence of additional malignant lesions. For decades, treatment has been based on high-dose radiation, but studies exploring the potential benefit of systemic therapies for high-risk patients are urgently needed. In this review, a panel of expert European hematologists updates the recommendations on the diagnosis and management of patients with solitary plasmacytoma.

Whole-body ultra-low dose CT using spectral shaping for detection of osteolytic lesion in multiple myeloma

OBJECTIVES

The aim of this study was to investigate the radiation dose and image quality of a whole-body low-dose CT (WBLDCT) using spectral shaping at 100 kV (Sn 100 kV) for the assessment of osteolytic lesions in patients with multiple myeloma.

METHODS

Thirty consecutive patients were retrospectively selected, who underwent a WBLDCT on a third-generation dual-source CT (DSCT) (Sn 100 kV, ref. mAs: 130). They were matched with patients, who were examined on a second-generation DSCT with a standard low-dose protocol (100 kV, ref. mAs: 111). Objective and subjective image quality, radiation exposure as well as the frequency of osteolytic lesions were evaluated.

RESULTS

All scans were of diagnostic image quality. Subjective overall image quality was significantly higher in the study group (p = 0.0003). Objective image analysis revealed that signal intensities, signal-to-noise ratio and contrast-to-noise ratio of the bony structures were equal or significantly higher in the control group. There was no significant difference in the frequency of osteolytic lesions (p = 0.259). The median effective dose of the study protocol was significantly lower (1.45 mSv vs. 5.65 mSv; p < 0.0001).

CONCLUSION

WBLDCT with Sn 100 kV can obtain sufficient image quality for the depiction of osteolytic lesions while reducing the radiation dose by approximately 74%.

KEY POINTS

• Spectral shaping using tin filtration is beneficial for whole-body low-dose CT • Sn 100 kV yields sufficient image quality for depiction of osteolytic lesions • Whole-body low-dose CT can be performed with a median dose of 1.5 mSv.

Automatic digital quantification of bone marrow myeloma volume in appendicular skeletons - clinical implications and prognostic significance

Multiple myeloma (MM) is a clonal plasma cell disorder originating in bone marrow. Whole body low-dose multidetector CT (MDCT) can depict bone marrow infiltration by myeloma cells into the adipose-rich fatty marrow of the appendicular skeleton. However, automated and objective volume measurement of bone marrow infiltration has not been established, and its clinical relevance remains unclear. We therefore developed novel CT post-processing software (MABLE software) and measured the total sum of CT values (cumulative CT value, cCTv) representing bone marrow infiltration, by combining volume and voxel-based CT values. The cCTv was greater in patients with symptomatic MM than in those with smouldering MM or monoclonal gammopathy of unknown significance. Patients with revised International Staging System (R-ISS) III had a higher cCTv than those with R-ISS I or II. Age, albumin, and M-protein levels independently predicted cCTv. Mixed graphical model analysis revealed direct relationships between cCTv and age or R-ISS. Tree-structured survival analysis and multivariate Cox analysis revealed that a cCTv greater than or equal to 4.4 was independently prognostic for overall survival. Anti-myeloma therapy reduced cCTv after treatment. These findings suggest that the automatically calculated cCTv reflects disease aggressiveness and is useful for accurate prognostic prediction in MM patients.

Myeloma and Bone Disease

PURPOSE OF REVIEW

Bone disease is a defining characteristic of multiple myeloma (MM) and the major cause of morbidity. It manifests as lytic lesions or osteopenia and is often associated with severe pain, pathological fracture, spinal cord compression, vertebral collapse, and hypercalcemia. Here, we have reviewed recent data on understanding its biology and treatment.

RECENT FINDINGS

The imbalance between bone regeneration and bone resorption underlies the pathogenesis of osteolytic bone disease. Increased osteoclast proliferation and activity accompanied by inhibition of bone-forming osteoblasts leads to progressive bone loss and lytic lesions. Although tremendous progress has been made, MM remains an incurable disease. Novel agents targeting bone disease are under investigation with the goal of not only preventing bone loss and improving bone quality but also harnessing MM tumor growth. Current data illustrate that the interactions between MM cells and the tumor-bone microenvironment contribute to the bone disease and continued MM progression. A better understanding of this microenvironment is critical for novel therapeutic treatments of both MM and associated bone disease.

Whole-body computed tomography versus conventional skeletal survey in patients with multiple myeloma: a study of the International Myeloma Working Group

For decades, conventional skeletal survey (CSS) has been the standard imaging technique for multiple myeloma (MM). However, recently whole-body computed tomography (WBCT) has been implemented into the diagnostic criteria of MM. This analysis compares sensitivity and prognostic significance of WBCT and CSS in patients with smoldering MM (SMM) and MM. Fifty-four of 212 patients (25.5%) had a negative CSS and a positive WBCT for osteolytic lesions (P<0.0001). Of 66 patients with SMM based on CSS, 12 (22.2%) had osteolytic lesions on WBCT. In comparison, WBCT failed to detect some bone destructions in the appendicular skeleton possibly due to limitations of the field of view. Presence of lytic bone lesions in WBCT was of borderline prognostic significance (P=0.051) for SMM patients, with a median time to progression of 38 versus 82 months for those without bone destructions. In conclusion, WBCT identifies significantly more sites of bone destruction than CSS. More than 20% of patients with SMM according to CSS have in fact active MM detectable with WBCT. On the basis of this and other studies, WBCT (either computed tomography (CT) alone or as part of a positron emission tomography-CT protocol) should be considered the current standard for the detection of osteolytic lesions in MM.

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.

Guidelines for the use of imaging in the management of patients with myeloma

The role of imaging in myeloma has gained increasing importance over the past few years. The recently revised definition of myeloma from the International Myeloma Working Group (IMWG) includes cross sectional imaging as a method to define bone disease and also incorporates its use in the disease definition for patients with suspected smouldering myeloma. The National Institute for Health and Care Excellence myeloma guidelines also recommend cross sectional imaging for patients with suspected myeloma. There is also increasing use of imaging in disease assessments and the International Myeloma Working Group has recently incorporated imaging in defining new response categories of minimal residual disease negativity, with or without imaging-based evidence of disease. Plain X-rays have previously been the standard imaging modality included in a myeloma work up at presentation but evidence is mounting for use of cross-sectional modalities such as computed tomography (CT), magnetic resonance imaging (MRI) and 18 fluoro-deoxyglucose (18 F-FDG) positron emission tomography (PET)/CT. Funding and therefore availability of newer imaging techniques remains a barrier. Here, we propose an evidence-based approach to the use and technical application of the latest imaging modalities at diagnosis and in the follow-up of patients with myeloma and plasmacytoma.

Whole-Body Low-Dose Computed Tomography (WBLDCT) in Assessment of Patients with Multiple Myeloma - Pilot Study and Standard Imaging Protocol Suggestion

BACKGROUND

For decades, the main imaging tool in multiple myeloma (MM) patients was plain radiography. However, computed tomography (CT) has been included in the updated criteria of MM. The main disadvantage of CT is a considerably high radiation dose. Therefore, low-dose CT protocols could be a solution. The aim of the study was to (1) preliminarily analyse the usefulness of Whole-Body Low-Dose CT (WBLDCT) in the evaluation of patients with MM and (2) to make adjustments in the standard CT imaging protocol.

MATERIAL/METHODS

In 41 patients with MM, WBLDCT was performed. The following parameters were used: detector configuration - 80×0.5 mm, scanning range in a single spiral acquisition from the skull to the proximal femoral bones, tube voltage - 120 kVp, current tube time product - 86 mAs, slice thickness 1 mm. Two sets of axial images were reconstructed for bone and soft tissue assessment, respectively. Secondary coronal and sagittal reconstructions were generated. Typical MM features were analysed and qualitatively compared with radiography results.

RESULTS

A potentially increased sensitivity of CT, as compared to radiography, in detecting lytic foci obscured by other structures or with a small degree of destruction was seen. A potentially increased specificity of CT was found in detecting cases of small foci suspicious of lytic lesions on skull radiographs, seen as arachnoid granulations fovea in CT. The following radiation parameters were recorded: max. CTDIvol - 7.4 mGy and DLP - 660-810 mGy×cm. WBLDCT was much shorter and more convenient to patients.

CONCLUSIONS

WBLDCT may become a valuable part of the assessment of MM features at a much lower radiation dose compared to standard CT protocols. It has a potential ability to increase diagnostic accuracy compared to radiography.

CIK Cells and HDAC Inhibitors in Multiple Myeloma

Multiple myeloma is the second most common hematological malignancy. Despite all the progress made in treating multiple myeloma, it still remains an incurable disease. Patients are left with a median survival of 4–5 years. The combined treatment of multiple myeloma with histone deacetylase inhibitors and cytokine-induced killer cells provides a promising targeted treatment option for patients. This study investigated the impact of a combined treatment compared to treatment with histone deacetylase inhibitors. The experiments revealed that a treatment with histone deacetylase (HDAC) inhibitors could reduce cell viability to 59% for KMS 18 cell line and 46% for the U-266 cell line. The combined treatment led to a decrease of cell viability to 33% for KMS 18 and 27% for the U-266 cell line, thus showing a significantly better efficacy than the single treatment.

Whole-body low-dose computed tomography in multiple myeloma staging: Superior diagnostic performance in the detection of bone lesions, vertebral compression fractures, rib fractures and extraskeletal findings compared to radiography with similar radiation exposure

The primary objective of the present prospective study was to compare the diagnostic performance of conventional radiography (CR) and whole-body low-dose computed tomography (WBLDCT) with a comparable radiation dose reconstructed using hybrid iterative reconstruction technique, in terms of the detection of bone lesions, skeletal fractures, vertebral compressions and extraskeletal findings. The secondary objective was to evaluate lesion attenuation in relation to its size. A total of 74 patients underwent same-day skeletal survey by CR and WBLDCT. In CR and WBLDCT, two readers assessed the number of osteolytic lesions at each region and stage according to the International Myeloma Working Group (IMWG) criteria. A single reader additionally assessed extraskeletal findings and their significance, the number of vertebral compressions and bone fractures. The radiation exposure was 2.7±0.9 mSv for WBLDCT and 2.5±0.9 mSv for CR (P=0.054). CR detected bone involvement in 127 out of 486 regions (26%; P<0.0001), confirmed by WBLDCT. CR underestimated the disease stage in 16% and overestimated it in 8% of the patients (P=0.0077). WBLDCT detected more rib fractures compared with CR (188 vs. 47; P<0.0001), vertebral compressions (93 vs. 67; P=0.010) and extraskeletal findings (194 vs. 52; P<0.0001). There was no correlation observed between lesion size (≥5 mm) and its attenuation (r=-0.006; P=0.93). The inter-observer agreement for the presence of osteolytic lesions was κ=0.76 for WBLDCT, and κ=0.55 for CR. The present study concluded that WBLDCT with hybrid iterative reconstruction technique demonstrates superiority to CR with an identical radiation dose in the detection of bone lesions, skeletal fractures, vertebral compressions and extraskeletal findings, which results in up- or downstaging in 24% patients according to the IMWG criteria. The attenuation of osteolytic lesions can be measured with the avoidance of the partial volume effect.

The Role of Imaging in the Treatment of Patients With Multiple Myeloma in 2016

The novel criteria for the diagnosis of symptomatic multiple myeloma have revealed the value of modern imaging for the management of patients with myeloma. Whole-body low-dose CT (LDCT) has increased sensitivity over conventional radiography for the detection of osteolytic lesions, and several myeloma organizations and institutions have suggested that whole-body LDCT should replace conventional radiography for the work-up of patients with myeloma. MRI is the best imaging method for the depiction of marrow infiltration by myeloma cells. Whole-body MRI (or at least MRI of the spine and pelvis if whole-body MRI is not available) should be performed for all patients with smoldering multiple myeloma with no lytic lesions to look for occult disease, which may justify treatment. In addition, MRI accurately illustrates the presence of plasmacytomas, spinal cord, and/or nerve compression for surgical intervention or radiation therapy; it is also recommended for the work-up of solitary bone plasmacytoma, and it may distinguish malignant from benign fractures (which is very important in cases of patients in biochemical remission with no other signs of progression). Diffusion weighted imaging (DWI) seems to improve MRI diagnosis in patients with myeloma. PET/CT is a functional imaging technique, more sensitive than conventional radiography for the detection of lytic lesions, which probably allows better definition of complete response and minimal residual disease compared with all other imaging methods. PET/CT has shown the best results in the follow-up of patients with myeloma and has an independent prognostic value both at diagnosis and following treatment. PET/CT can also be used for the work-up of solitary bone plasmacytoma and nonsecretory myeloma.

Bone mineral density utilization in patients with newly diagnosed multiple myeloma

Bone disease is a major cause for morbidity in multiple myeloma (MM), with the main focus concerning the manifestation as osteolytic lesions. Bone mineral loss is another reflection of myeloma bone involvement. Recently, osteoporosis has been omitted as a defining criterion for symptomatic disease in MM. We conducted a retrospective study to evaluate the use of bone mineral density (BMD) exams by dual-energy X-ray absorptiometry (DXA) among MM patients in a tertiary medical care centre. One-hundred seventy three patients were included. The T-scores of lumbar spine (LS), left femur neck (FN) and left total hip (TH) were obtained and analysed. The extent of osteolytic disease was categorized based on six bony areas. There was a strong correlation between spine and femur's T-scores (r = 0.56-0.61, p < 0.0001), although different sets of variables were correlated with LS and femur's T-scores. There was no correlation between BMD measurements and osteolytic disease extent. Patients with vertebral fracture(s) had significant lower T-scores of the spine in comparison to patients without vertebral fractures. Sixty-three patients (36.4% of the cohort) had follow-up DXA exam. In general, there was an increase in the LS T-scores, while femoral values decreased. However, in patients who achieved complete response (CR) and in those who retained CR during follow-up, femoral BMD increased as well. Because correlation between BMD and the extent of osteolytic lesions was not seen, our data support the recent exclusion of BMD assessment from the definition of symptomatic myeloma. Still, its use should be considered for evaluation of age- or therapy-related osteoporosis. Copyright © 2016 John Wiley & Sons, Ltd.

The diagnostic imaging of bone metastases

BACKGROUND

Skeletal metastases are the most common malignant tumor in bone. Certain types of cancer (e.g., of the prostate or breast) are particularly likely to give rise to skeletal metastases, with prevalences of up to 70%. The diagnosis of skeletal metastases has a major impact on the overall treatment strategy and is an important determinant of the course of illness and the quality of life. The goal of diagnostic imaging is to detect skeletal metastases early, whenever they are suspected on the basis of clinical or laboratory findings or in patients who are at high risk. Other important issues include assessment of the risk of fracture and the response to treatment.

METHODS

This review is based on selected pertinent articles published up to December 2013.

RESULTS

Projectional radiography (plain films) is still useful for the immediate investigation of symptomatic bone pain and for the assessment of stability. Skeletal scintigraphy, the classic screening test for patients with cancer who do not have bone pain (specificity 81%, sensitivity 86%), has now been supplemented-in some cases, replaced-by other techniques. CT, including lowdose CT, is used to detect changes in bone structure due to metastases of some types of primary tumor (specificity 95%, sensitivity 73%); whole-body MRI, to detect metastases in the bone marrow and extraosseous soft tissues, e.g., metastases compressing the spinal cord (specificity 95%, sensitivity 91%); PET-CT, to detect metabolically active tumors (specificity 97%, sensitivity 90%).

CONCLUSION

Different imaging modalities are often used in combination to detect bone metastases optimally. Owing to advances in modern tomographic imaging, the current trend is toward whole-body imaging in a single session. The choice of method is based on the clinical situation and the type of primary tumor. Further research should address the impact of these costly and laborintensive imaging methods on treatment strategies and on the course of illness.