Magnetic resonance imaging in the staging of solitary plasmacytoma of bone

Imaging finding of multiple myeloma presenting as soft-tissue disease mimicking extrapleural space tumors: A case report

Extramedullary involvement of multiple myeloma is an uncommon and aggressive condition characterized by proliferation of monoclonal plasma cells located outside the bone marrow. This report describes the imaging findings of a patient who presented with continuous soft-tissue disease on the ribs, suspected as extrapleural space tumors on chest CT. The patient was diagnosed with multiple myeloma through surgical biopsy of the tumor and bone marrow.

Solitary Bone Plasmacytoma of Humerus Presenting as a Nonhealing Fracture in a Child: A Rare Entity

Solitary bone plasmacytoma is an extremely rare entity and is characterized by localized proliferation of monoclonal plasma cells. Plasmacytomas are extremely rare in the pediatric population. The median age at diagnosis is usually the fifth or sixth decade, with axial skeleton being more commonly involved than appendicular. We hereby, report the case of a 13-year-old boy with solitary bone plasmacytoma of the right humerus. Though extremely rare in the pediatric age group, plasmacytomas may be considered as one of the remote differentials in children presenting with solitary bone tumors.

Case Report: Suspected Solitary Osseous Plasmacytoma in a Cat: Use of Magnetic Resonance Imaging to Diagnose and Confirm Resolution of Disease Following Chemotherapy

A 9-year-old female spayed Domestic Shorthair cat presented for pain, reluctance to jump, and hyporexia of 14 days duration. Neurologic examination was consistent with C6-T2 myelopathy. Magnetic resonance imaging (MRI) revealed a solitary, contrast-enhancing lesion within the T2 vertebral body. Solitary osseous plasmacytoma was diagnosed based on neurologic examination, advanced imaging, and clinicopathologic findings. Melphalan and prednisolone therapy were initiated. Complete resolution of clinical signs and the vertebral lesion were documented at a 2-year follow up examination with neurologic examination and repeat spinal MRI, respectively. Solitary osseous plasmacytoma are rare neoplasms in humans and domestic animals. As such, there is a paucity of published information regarding diagnostic criteria, MRI findings, treatment modalities, progression, and remission of disease in the feline patient. Most data are extrapolated from human medicine. The purpose of this report is to document neurologic exam and MR findings at the time of diagnosis and complete resolution of a solitary osseous vertebral plasmacytoma following melphalan and prednisolone therapy.

Successful treatment of solitary bladder plasmacytoma: A case report

BACKGROUND

Plasmacytoma is a rare neoplastic disorder that arises from B-lymphocytes. Solitary bladder plasmacytoma, a type of solitary extramedullary plasmacytoma, is even rarer. Treatments for solitary extramedullary plasmacytoma include surgery, chemotherapy, and radiation. However, there are no clinical trials or guidelines specifying which treatment might represent the gold standard.

CASE SUMMARY

We herein report a case of a 51-year-old woman with solitary bladder plasmacytoma (SBP). There remains no consensus regarding the optimal treatment for SBP. However, we successfully treated her with transurethral resection of bladder tumor followed by postoperative radiotherapy (50 Gy/25 F). The patient remained free of tumor recurrence at a 7-mo follow-up.

CONCLUSION

Radiation is the potential main treatment for SBP. However, surgery is also necessary.

Spinal cord compression due to a solitary, bulky plasmacytoma of posterior mediastinum

Solitary plasmacytoma is a rare clonal plasma cell tumor, representing 2-5% of plasma cell disorders. The standard treatment is local radiotherapy. However, in some cases, its use is limited by the size and/or location of the mass. Systemic chemotherapy may be a useful therapeutic alternative. We describe a case of a 27-year-old male with a bulky solitary plasmacytoma arising in the posterior mediastinum, causing spinal cord compression. Radiotherapy was considered risky as the mass was located in the heart and left lung fields. Systemic treatment was given. After the first cycle of cyclophosphamide, bortezomib, and dexamethasone (VCD), the patient attained full neurological recovery. After four VCD cycles, complete remission was achieved. Autologous stem cell transplantation was given as consolidation therapy. At 3 months post-transplantation, the patient is in full clinical recovery and complete metabolic remission on 18FDG PET-CT. Although infrequent, plasma cell disorders must be considered in adult patients with a bulky tumoral mass in the posterior mediastinum. PET-CT is the whole-body imaging technique of choice to detect SP, to evaluate response to treatment and during follow-up.

Long-term Outcomes After Definitive Radiation Therapy for Solitary Plasmacytoma

OBJECTIVE

Definitive radiotherapy (RT) with or without surgery is the standard of care for solitary plasmacytoma. Here, we report clinical outcomes for this rare malignant neoplasm.

PATIENTS AND METHODS

We retrospectively reviewed the medical records of adults with solitary plasmacytoma treated with definitive RT between 1963 and 2015 at a single institution, and assessed disease control, survival, and toxicity per Common Terminology Criteria for Adverse Events (CTCAE), version 4.

RESULTS

A total of 42 patients with solitary plasmacytoma of the bone (SPB, n=27) or extramedullary plasmacytoma (EMP, n=15) were treated with definitive RT with (n=11) or without (n=31) surgical resection. The median age at diagnosis was 59 years (range: 28 to 76 y).Twenty-two patients had tumors ≥5 cm and 20 had tumors <5 cm. Immunoglobulins were elevated in 23 patients and M-protein in 14. The median RT dose was 45 Gy (range: 15 to 54 Gy) over a median 25 fractions (range: 1 to 38 fractions) with 3 patients receiving twice-daily fractionation and 6 received elective nodal irradiation. No patients received adjuvant chemotherapy. The median follow-up was 10.3 years. The 10-year local control rate after RT was 88%. Five patients who developed a local recurrence had SPB ≥5 cm. The 10-year multiple myeloma-free survival rates were: overall, 47%; SPB, 24%; and EMP, 87% (P=0.0012). The 10-year cause-specific survival rate was 75%: 64% for SPB versus 93% for EMP (P=0.0116). The 10-year overall survival rate was 60%. Three patients experienced late grade 2+ toxicity.

CONCLUSIONS

Definitive RT with moderate doses results in excellent local control. We observed a higher rate of progression to multiple myeloma and lower survival in patients with SPB compared with EMP.

Solitary plasmacytoma of jaw bone: A case report and systematic review of fifty cases from literature

Solitary plasmacytoma of bone (SPB) is a localized form of plasma cell neoplasm where jaw involvement is rare. Distinguishing SPB from other plasma cell neoplasms is critical for treatment and survival. Here, a case of SPB of mandible in an elderly female is reported. Histopathological diagnosis of plasma cell neoplasm was confirmed immunohistochemically with MUM1 and CD138 positivity and multiple myeloma (MM) was ruled out on performing systemic workup. Prognosis of SPB worsens when it transforms into MM. A systematic review was undertaken with the objective to determine the factors affecting conversion of SPB to MM. An electronic search was undertaken with PubMed/MEDLINE, Web of Science and Science Direct. Fifty cases of SPB of jaw from 29 publications were reviewed. SPB commonly presents as a painless swelling. Radiographically, it is commonly seen as multilocular radiolucency with well-defined borders. Follow-up data showed that nine cases turned into MM in a mean duration of 1 year 9 months and 12 patients died after median disease-free survival of 6 years 9 months. Prognosis of SPB is found to be affected by tumor size (≥5 cm), anaplasia of tumor cells, Ki-67 labeling index, vascularity of the tumor, presence of clonal bone marrow plasma cells, serum immune globulin level, dose of radiotherapy and persistence of M protein after treatment. There is a need to identify prognostic subgroups in SPB based on these factors. Furthermore, studies are necessary for standardization of treatment protocol to halt or prolong the progression of SPB to MM.

Radiotherapy for the treatment of solitary plasmacytoma: 7-year outcomes by a mono-institutional experience

OBJECTIVES

Solitary plasmacytoma (SP) is characterized by a single mass of clonal plasma cells. Definitive RT can result in long-term local control of the SP. Due to the small number of patients and narrow range of doses, phase III randomized trials are lacking. The aim of this study is to further support the potential use of RT for the treatment of SP.

METHODS

Clinical data of all patients treated for SP at our Institution between 1992 and 2018 were reviewed. A total of 42 consecutive patients were analyzed.

RESULTS

The median follow-up was 84.8 months. Radiation dose did not differ significantly as a function of sex, type of SP (solitary bone plasmacytoma or as extramedullary plasmacytoma), tumor size; conversely differs significantly as a function of age (p = 0.04). The 5y-OS and 10y-OS were, respectively, 96 and 91%. Local recurrences developed in 21.4% of patients (9/42). 16 patients progressed to MM (38.1%). The 5y-progression to MM free survival (PMFS) and the 10y-PMFS were, respectively, 68.6 and 61.9%.

CONCLUSIONS

Our data confirm that good results are achievable with RT to treat SP, but they don't allow defining a dose-effect correlation; therefore, it remains uncertain which is the most effective dose and whether lower doses can guarantee adequate disease control.

18F-FDG PET or PET/CT role in plasmacytoma: A systematic review

BACKGROUND

The metabolic behavior of plasmacytoma at ¹⁸F-FDG PET/CT is not yet clear.

OBJECTIVE

The aim of this systematic review was to analyze published data about the role of ¹⁸F-FDG PET or PET/CT in patients affected by plasmacytoma.

METHODS

Acomprehensive computer literature search of the Scopus, PubMed/MEDLINE, Embase and Cochrane Library databases was conducted including articles up to July 2019 to find relevant published papers about the performance of ¹⁸F-FDG PET and PET/CT in plasmacytoma.

RESULTS

The comprehensive computer literature search revealed 371 articles. On reviewing the titles and abstracts, 363 articles were excluded because the reported data were not within the field of interest of this review. Eight articles were selected and retrieved in full-text version. From the analyses of the selected studies, the following main findings have been founded: 1) plasmacytoma generally is a ¹⁸F-FDG-avid tumor and PET/CT had good diagnostic performance with high sensitivity; 2) ¹⁸F-FDG PET/CT influenced patient management in most cases avoiding useless therapies and choosing the best therapeutic approach; 3) prognostic value of PET/CT qualitative and semiquantitative parameters is only suggested with controversial reports.

CONCLUSION

Despite several limitations affect this analysis, especially related to the low number of articles and patients studied, plasmacytoma looks to be an ¹⁸F-FDG-avid tumor in most of the cases; ¹⁸F-FDG PET or PET/CT had good diagnostic performance and had a significant clinical impact in change of therapeutic approach. Moreover, a possible prognostic role of PET/CT features is described.

Guidelines for Acquisition, Interpretation, and Reporting of Whole-Body MRI in Myeloma: Myeloma Response Assessment and Diagnosis System (MY-RADS)

Acknowledging the increasingly important role of whole-body MRI for directing patient care in myeloma, a multidisciplinary, international, and expert panel of radiologists, medical physicists, and hematologists with specific expertise in whole-body MRI in myeloma convened to discuss the technical performance standards, merits, and limitations of currently available imaging methods. Following guidance from the International Myeloma Working Group and the National Institute for Clinical Excellence in the United Kingdom, the Myeloma Response Assessment and Diagnosis System (or MY-RADS) imaging recommendations are designed to promote standardization and diminish variations in the acquisition, interpretation, and reporting of whole-body MRI in myeloma and allow response assessment. This consensus proposes a core clinical protocol for whole-body MRI and an extended protocol for advanced assessments. Published under a CC BY 4.0 license. Online supplemental material is available for this article.

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.

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.

How I treat elderly patients with plasma cell dyscrasias

Plasma cell dyscrasias are a rare heterogeneous group of hematological disorders which are more prevalent in the older part of the population. The introduction of novel agents, improved understanding of disease biology and better supportive management have improved outcomes considerably and in the era of the aging population the question of how to best manage older patients with plasma cell dyscrasias has never been more relevant. Data on how to treat these patients comes mostly from subgroup analysis as they are underrepresented in clinical trials. This review will cover issues, available evidence and recommendations relevant to diagnosis and management of the older patients with Multiple Myeloma (MM), Waldenstrom Macroglobulinemia (WM) and systemic AL Amyloidosis. What will become increasingly evident is the need to develop and establish the use of disease-specific geriatric assessment (GA) tools. Frailty status assessment using GA tools and moving away from making decisions based merely on chronological age will allow setting clear treatment goals and consequently achieving an optimum balance between effectiveness and toxicity for this complex and heterogeneous group of patients.

Radiation Therapy for Solitary Plasmacytoma and Multiple Myeloma: Guidelines From the International Lymphoma Radiation Oncology Group

PURPOSE

To develop guidelines for the work-up and radiation therapy (RT) management of patients with plasma cell neoplasms.

METHODS AND MATERIALS

A literature review was conducted covering staging, work-up, and RT management of plasma cell neoplasms. Guidelines were developed through consensus by an international panel of radiation oncologists with expertise in these diseases, from the International Lymphoma Radiation Oncology Group. RT volume definitions are based on the International Commission on Radiation Units and Measurements.

RESULTS

Plasma cell neoplasms account for approximately one-fifth of mature B-cell neoplasms in the United States. The majority (∼95%) are diagnosed as multiple myeloma, in which there has been tremendous progress in systemic therapy approaches with novel drugs over the last 2 decades, resulting in improvements in disease control and survival. In contrast, a small proportion of patients with plasma cell neoplasms present with a localized plasmacytoma in the bone, or in extramedullary (extraosseous) soft tissues, and definitive RT is the standard treatment. RT provides long-term local control in the solitary bone plasmacytomas and is potentially curative in the extramedullary cases. This guideline reviews the diagnostic work-up, principles, and indications for RT, target volume definition, treatment planning, and follow-up procedures for solitary plasmacytoma. Specifically, detailed recommendations for RT volumes and dose/fractionation are provided, illustrated with specific case scenarios. The role of palliative RT in multiple myeloma is also discussed.

CONCLUSIONS

The International Lymphoma Radiation Oncology Group presents a standardized approach to the use and implementation of definitive RT in solitary plasmacytomas. The modern principles outlining the supportive role of palliative RT in multiple myeloma in an era of novel systemic therapies are also discussed.

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.

Advanced Imaging of Multiple Myeloma Bone Disease

Multiple myeloma (MM), a malignancy of mature plasma cells, is the second most common hematologic malignancy and the most frequent cancer to involve the skeleton (1, 2). Bone disease in MM patients is characterized by lytic bone lesions that can result in pathologic fractures and severe pain. While recent advances in MM therapy have significantly increased the median survival of newly diagnosed patients (3), skeletal lesions and their sequelae continue to be a major source of patient morbidity and mortality and bone pain is the most frequent presenting symptom of MM patients (4). Rapid improvements in imaging technology now allow physicians to identify ever smaller skeletal and bone marrow abnormalities, however the clinical value of subtle radiographic findings is not always clear. This review summarizes currently available technologies for assessing MM bone disease and provides guidance for how to choose between imaging modalities.

Asymptomatic solitary bladder plasmocytoma: A case report and literature review

RATIONALE

Solitary extramedullary plasmocytoma may arise in any organ, either as a primary tumor or as part of a systemic myeloma; if it rarely affects bladder, it presents with urinary symptoms. We describe the first case of asymptomatic BP occasionally diagnosed in a patient with ascites.

PATIENT CONCERNS

A 74-year-old woman with hepatitis C virus (HCV)-related liver cirrhosis presented with ascites and no urinary or other symptoms.

DIAGNOSES

Routine blood tests were within normal ranges, except for mild elevation of transaminases due to chronic hepatitis. Abdominal ultrasound and computed tomography (CT) scanning showed multiple liver nodules suspected for carcinomas and, incidentally, a 18 mm solid lesion of right bladder wall.

OUTCOMES

She underwent transurethral resection of the bladder tumor and percutaneous liver biopsies; final diagnosis was solitary bladder plasmocytoma (BP) and hepatocellular carcinoma (HCC), respectively. She was given chemoembolization of the main HCC nodule but no adjuvant treatment for BP. At 3-month follow-up, total-body CT showed no signs of bladder disease nor distant metastases; unfortunately, she died one month later due to liver failure.

LESSONS

This is the first reported case of asymptomatic BP. This rare neoplasm may pose difficulties in differential diagnosis with both bladder metastases and the plasmocytoid variant of bladder transitional cell carcinoma. We also highlighted lack of factors predicting disease outcome as well as response to potential adjuvant treatments.

Solitary Plasmacytoma

Solitary plasmacytoma is a rare disease characterized by a localized proliferation of neoplastic monoclonal plasma cells, without evidence of systemic disease. It can be subdivided into solitary bone plasmacytoma if the lesion originates in bone, or solitary extramedullary plasmacytoma if the lesion involves a soft tissue. The incidence of solitary bone plasmacytoma is higher than solitary extramedullary plasmacytoma. Also, the prognosis is different: even if both forms respond well to treatment, overall survival and progression-free survival of solitary bone plasmacytoma are poorer than solitary extramedullary plasmacytoma due to its higher rate of evolution in multiple myeloma. However, the recent advances in the diagnosis of multiple myeloma can better refine also the diagnosis of plasmacytoma. Flow cytometry studies and molecular analysis may reveal clonal plasma cells in the bone marrow; magnetic resonance imaging or 18 Fluorodeoxyglucose positron emission tomography could better define osteolytic bone lesions. A more explicit exclusion of possible occult systemic involvement can avoid cases of misdiagnosed multiple myeloma patients, which were previously considered solitary plasmacytoma and less treated, with an unavoidable poor prognosis.

Due to the rarity of the disease, there is no uniform consensus about prognostic factors and treatment. Radiotherapy is the treatment of choice; however, some authors debate about the radiotherapy dose and the relationship with the response rate. Moreover, the role of surgery and chemotherapy is still under debate. Nevertheless, we must consider that the majority of studies include a small number of patients and analyze the efficacy of conventional chemotherapy; few cases are reported concerning the efficacy of novel agents.

18F-FDG PET/CT in solitary plasmacytoma: metabolic behavior and progression to multiple myeloma

PURPOSE

Solitary plasmacytoma (SP) is a rare plasma-cell neoplasm, which can develop both in skeletal and/or soft tissue and frequently progresses to multiple myeloma (MM). Our aim was to study the metabolic behavior of SP and the role of 18F-FDG-PET/CT in predicting progression to MM.

MATERIALS AND METHODS

Sixty-two patients with SP who underwent 18F-FDG-PET/CT before any treatment were included. PET images were qualitatively and semiquantitatively analyzed by measuring the maximum standardized uptake value body weight (SUVbw), lean body mass (SUVlbm), body surface area (SUVbsa), metabolic tumor volume (MTV), total lesion glycolysis (TLG) and compared with age, sex, site of primary disease, and tumor size.

RESULTS

Fifty-one patients had positive 18F-FDG-PET/CT (average SUVbw was 8.3 ± 4.7; SUVlbm 5.8 ± 2.6; SUVbsa 2 ± 1; MTV 45.4 ± 37; TLG 227 ± 114); the remaining 11 were not 18F-FDG-avid. Tumor size was significantly higher in patients avid lesions compared to FDG not avid; no other features are associated with FDG-avidity. Progression to MM occurred in 29 patients with an average of 18.3 months; MM was more likely to develop in patients with bone plasmacytoma and in patients with 18F-FDG avid lesion. Time to transformation in MM (TTMM) was significantly shorter in patients with osseous SP, in 18F-FDG avid lesion, for SUVlbm > 5.2 and SUVbsa > 1.7.

CONCLUSIONS

18F-FDG pathological uptake in SP occurred in most cases, being independently associated with tumor size. PET/CT seemed to be correlated to a higher risk of transformation in MM, in particular for 18F-FDG avid plasmacytoma and SBP. Among semiquantitative features, SUVlbm > 5.2 and SUVbsa > 1.7 were significantly correlated with TTMM.

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.

Role of 18F-FDG PET/CT in the diagnosis and management of multiple myeloma and other plasma cell disorders: a consensus statement by the International Myeloma Working Group

The International Myeloma Working Group consensus aimed to provide recommendations for the optimal use of ¹⁸fluorodeoxyglucose (¹⁸F-FDG) PET/CT in patients with multiple myeloma and other plasma cell disorders, including smouldering multiple myeloma and solitary plasmacytoma. ¹⁸F-FDG PET/CT can be considered a valuable tool for the work-up of patients with both newly diagnosed and relapsed or refractory multiple myeloma because it assesses bone damage with relatively high sensitivity and specificity, and detects extramedullary sites of proliferating clonal plasma cells while providing important prognostic information. The use of ¹⁸F-FDG PET/CT is mandatory to confirm a suspected diagnosis of solitary plasmacytoma, provided that whole-body MRI is unable to be performed, and to distinguish between smouldering and active multiple myeloma, if whole-body X-ray (WBXR) is negative and whole-body MRI is unavailable. Based on the ability of ¹⁸F-FDG PET/CT to distinguish between metabolically active and inactive disease, this technique is now the preferred functional imaging modality to evaluate and to monitor the effect of therapy on myeloma-cell metabolism. Changes in FDG avidity can provide an earlier evaluation of response to therapy compared to MRI scans, and can predict outcomes, particularly for patients who are eligible to receive autologous stem-cell transplantation. ¹⁸F-FDG PET/CT can be coupled with sensitive bone marrow-based techniques to detect minimal residual disease (MRD) inside and outside the bone marrow, helping to identify those patients who are defined as having imaging MRD negativity.

Multiple myeloma of the spine

Radiology provides a crucial clinical adjunct in patients with plasma cell disorders, in particular multiple myeloma, and its uses are evolving and expanding. This pictorial review illustrates the role of imaging throughout the patient's clinical course, with specific reference to recently updated international diagnostic criteria. At presentation, imaging optimises characterisation and staging of the plasma-cell disorder, while later in the course of the disease, its roles include the monitoring of disease progression, assessment of post-treatment response and the investigation of clinical deterioration.

Musculoskeletal Imaging Findings of Hematologic Malignancies

Hematologic malignancies comprise a set of prevalent yet clinically diverse diseases that can affect every organ system. Because blood components originate in bone marrow, it is no surprise that bone marrow is a common location for both primary and metastatic hematologic neoplasms. Findings of hematologic malignancy can be seen with most imaging modalities including radiography, computed tomography (CT), technetium 99m (^99mTc) methylene diphosphonate (MDP) bone scanning, fluorine 18 (¹⁸F) fluorodeoxyglucose (FDG) positron emission tomography (PET)/CT, and magnetic resonance (MR) imaging. Because of the diversity of imaging appearances and clinical behavior of this spectrum of disease, diagnosis can be challenging, and profound understanding of the underlying pathophysiologic changes and current treatment modalities can be daunting. The appearance of normal bone marrow at MR imaging and FDG PET/CT is also varied due to dynamic compositional changes with normal aging and in response to hematologic demand or treatment, which can lead to false-positive interpretation of imaging studies. In this article, the authors review the normal maturation and imaging appearance of bone marrow. Focusing on lymphoma, leukemia, and multiple myeloma, they present the spectrum of imaging findings of hematologic malignancy affecting the musculoskeletal system and the current imaging tools available to the radiologist. They discuss the imaging findings of posttreatment bone marrow and review commonly used staging systems and consensus recommendations for appropriate imaging for staging, management, and assessment of clinical remission. ^©RSNA, 2017.

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.

Solitary extraosseous plasmacytoma

Plasma cell neoplasms are characterized by a neoplastic plasma cell lineage which produces a monoclonal immunoglobulin. These neoplasms can present as a single lesion (solitary plasmacytoma) or as multiple lesions (multiple myeloma). Solitary plasmacytomas most frequently occur in bone (plasmacytomas of bone), but can also be found outside bone in soft tissues (extramedullary plasmacytomas).

MR imaging and PET/CT in diagnosis and management of multiple myeloma

Multiple myeloma is a common hematologic malignancy among the elderly population. Although there have been many advances in treatment over the past few decades, the overall prognosis for the disease remains poor. Conventional radiography has long been the standard of reference for the imaging of multiple myeloma. However, 10%-20% of patients with multiple myeloma do not have evidence of disease at conventional radiography. There is a growing body of evidence supporting use of magnetic resonance (MR) imaging and 2-[fluorine-18]fluoro-2-deoxy-D-glucose (FDG) positron emission tomography (PET)/computed tomography (CT) in diagnosis and management of multiple myeloma. MR imaging is useful in detection of bone marrow infiltration, a finding often missed at conventional radiography. FDG PET/CT is especially sensitive for the detection of extramedullary disease and can help detect the metabolically active lesions that often precede evidence of osseous destruction at conventional radiography. MR imaging and FDG PET/CT are useful tools that can provide essential information for diagnosis and management of patients with multiple myeloma. Both modalities allow accurate localization of disease after chemotherapy or autologous stem cell transplantation and can provide important prognostic information that can influence further clinical decision making regarding therapy, particularly when tumor serum markers may be a less reliable indicator of disease burden after repeated treatments.

Early surgical occipitocervical stabilization for plasma cell neoplasms at the craniocervical junction: systematic review and proposal of a treatment algorithm

BACKGROUND CONTEXT

Plasma cell neoplasms (PCNs) of the craniocervical junction (CCJ) are rare. Because of their destructive growth, PCNs may induce spinal instability and harbor the risk of sudden death. Therefore, PCNs at the CCJ require special consideration. Although the commonly used primary treatment of PCN is radiotherapy (RT), treatment guidelines are inexistent for CCJ occurrences.

PURPOSE

This study aimed to conduct a systematic review of the literature, evaluate the benefit of early and extended surgical treatment followed by RT, and outline a treatment algorithm based on the data gathered.

STUDY DESIGN/SETTING

Case series and systematic review of all reported cases in the English, Spanish and German medical literature were carried out.

CASE SERIES

retrospective clinical study, tertiary care center (2004-2014). Patients with a lesion of the CCJ (C0-C2) were identified. Clinical charts, imaging data, operative reports, and follow-up data were analyzed.

REVIEW

a systematic literature review was performed using PubMed. Further manuscripts were identified by the web search engine Google.

RESULTS

Our series comprised four patients (one female, three males), mean age 58 years. There was one lesion of C1 and three of C2. Two patients with neck pain received vertebroplasty (C1 and C2, respectively) and RT as primary management. Both developed secondary instability of the CCJ after 12 and 5 months, respectively, and required occipitocervical stabilization (OCS). The other two patients underwent OCS and required no additional surgery and no signs of instability at follow-up. Forty-nine cases of OCS were published previously. Spinal stability was achieved significantly more frequently by OCS than by less invasive or medical interventional treatment options (p=.001; two-sided Fisher exact test).

CONCLUSIONS

Plasma cell neoplasms are highly radiosensitive. However, at the CCJ, a life-threatening instability may occur early and require surgical treatment. Based on personal experience, we favor OCS in this location. A systematic review of the literature supports this approach. We present a summary of our findings in a concise treatment algorithm for PCN of the CCJ.

Multiple Myeloma, Version 2.2016: Clinical Practice Guidelines in Oncology

Multiple myeloma (MM) is a malignant neoplasm of plasma cells that accumulate in bone marrow, leading to bone destruction and marrow failure. Recent statistics from the American Cancer Society indicate that the incidence of MM is increasing. The NCCN Clinical Practice Guidelines in Oncology (NCCN Guidelines) included in this issue address management of patients with solitary plasmacytoma and newly diagnosed MM.

Role of Magnetic Resonance Imaging in the Management of Patients With Multiple Myeloma: A Consensus Statement

Purpose

The aim of International Myeloma Working Group was to develop practical recommendations for the use of magnetic resonance imaging (MRI) in multiple myeloma (MM).

Methods

An interdisciplinary panel of clinical experts on MM and myeloma bone disease developed recommendations for the value of MRI based on data published through March 2014.

Recommendations

MRI has high sensitivity for the early detection of marrow infiltration by myeloma cells compared with other radiographic methods. Thus, MRI detects bone involvement in patients with myeloma much earlier than the myeloma-related bone destruction, with no radiation exposure. It is the gold standard for the imaging of axial skeleton, for the evaluation of painful lesions, and for distinguishing benign versus malignant osteoporotic vertebral fractures. MRI has the ability to detect spinal cord or nerve compression and presence of soft tissue masses, and it is recommended for the workup of solitary bone plasmacytoma. Regarding smoldering or asymptomatic myeloma, all patients should undergo whole-body MRI (WB-MRI; or spine and pelvic MRI if WB-MRI is not available), and if they have > one focal lesion of a diameter > 5 mm, they should be considered to have symptomatic disease that requires therapy. In cases of equivocal small lesions, a second MRI should be performed after 3 to 6 months, and if there is progression on MRI, the patient should be treated as having symptomatic myeloma. MRI at diagnosis of symptomatic patients and after treatment (mainly after autologous stem-cell transplantation) provides prognostic information; however, to date, this does not change treatment selection.

Multiple myeloma

This article presents a review of multiple myeloma, precursor states, and related plasma cell disorders. The clinical roles of fluorodeoxyglucose PET/computed tomography (CT) and the potential to improve the management of patients with multiple myeloma are discussed. The clinical and research data supporting the utility of PET/CT use in evaluating myeloma and other plasma cell dyscrasias continues to grow.

State of the art imaging of multiple myeloma: comparative review of FDG PET/CT imaging in various clinical settings

18-Flurodeoxyglucose Positron Emission Tomography with computed tomography (FDG PET/CT) and Magnetic Resonance Imaging (MRI) have higher sensitivity and specificity than whole-body X-ray (WBXR) survey in evaluating disease extent in patients with multiple myeloma (MM). Both modalities are now recommended by the Durie-Salmon Plus classification although the emphasis is more on MRI than PET/CT. The presence of extra-medullary disease (EMD) as evaluated by PET/CT imaging, initial SUVmax and number of focal lesions (FL) are deemed to be strong prognostic parameters at staging. MRI remains the most sensitive technique for the detection of diffuse bone marrow involvement in both the pre and post-therapy setting. Compression fractures are best characterized with MRI signal changes, for determining vertebroplasty candidates. While PET/CT allows for earlier and more specific evaluation of therapeutic efficacy compared to MRI, when signal abnormalities persist years after treatment. PET/CT interpretation, however, can be challenging in the vertebral column and pelvis as well as in cases with post-therapy changes. Hence, a reading approach combining the high sensitivity of MRI and superior specificity of FDG PET/CT would be preferred to increase the diagnostic accuracy. In summary, the established management methods in MM, mainly relying on biological tumor parameters should be complemented with functional imaging data, both at staging and restaging for optimal management of MM.

Multiparameter flow cytometry for staging of solitary bone plasmacytoma: new criteria for risk of progression to myeloma

MFC is a valuable biomarker to discriminate “true” SBP patients from those with “occult” BM clonal PCs and high-risk of progression to MM.

The role of positron emission tomography-computed tomography and magnetic resonance imaging in diagnosis and follow up of multiple myeloma

Multiple myeloma is the second most common hematologic malignancy and occurs most commonly in elderly patients. Almost all multiple myeloma patients develop bone lesions in the course of their disease or have evidence of bone loss at initial diagnosis. Whole-body conventional radiography remains the gold standard in the diagnostic evaluation, but computed tomography, magnetic resonance imaging and 18F-fluorodeoxyglucose positron emission tomography are increasingly used as complementary techniques in the detection of bone lesions. Moreover, the number of lesions detected and the presence of extramedullary disease give strong prognostic information. These new techniques may help to assess treatment response in solitary plasmacytoma or in multiple myeloma. In this article, we review recent data on the different imaging techniques used at diagnosis and in the assessment of treatment response, and discuss some current issues.

Cranial plasmacytoma: a case series and review of the literature

Plasmacytomas are malignant proliferations of plasma cells which can occur with different plasma cell dyscrasias. Solitary plasmacytomas of bone or extraosseous plasmacytomas, depending on the tissue of origin, develop in isolation without systemic manifestations of multiple myeloma. Three cases of cranial plasmacytomas are described, two in patients with multiple myeloma and one extraosseous plasmacytoma. Management options are discussed.

Imaging of myeloma: beyond lytic lesions

SUMMARY This review will focus on the imaging findings present in patients with typical symptomatic multiple myeloma. The emphasis will be on recent developments related to advanced imaging techniques. There are several different ways to stage or risk-stratify patients with symptomatic multiple myeloma after the diagnosis has been established. The International Myeloma Working Group issued a consensus statement regarding imaging of myeloma patients in 2009. The consensus was that the conventional radiographic survey should still be carried out as the baseline imaging study and that MRI should be added whenever possible. Many other imaging exams are available including: CT, PET/CT, MRI and sestamibi. The strengths and weaknesses of all of the available imaging techniques will be summarized.

Comparison of modern and conventional imaging techniques in establishing multiple myeloma-related bone disease: a systematic review

This systematic review of studies compared magnetic resonance imaging (MRI), (18) F-fluorodeoxyglucose positron emission tomography (FDG-PET), FDG-PET with computerized tomography (PET-CT) and CT with whole body X-Ray (WBXR) or (whole body) CT in order to provide evidence-based diagnostic guidelines in multiple myeloma bone disease. A comprehensive search of 3 bibliographic databases was performed; methodological quality was assessed using Quality Assessment of Diagnostic Accuracy Studies (QUADAS) criteria (score 1-14). Data from 32 directly comparative studies were extracted. The mean QUADAS score was 7·1 (3-11), with quality hampered mainly by a poor description of selection and execution criteria. All index tests had a higher detection rate when compared to WBXR, with up to 80% more lesions detected by the newer imaging techniques; MRI (1·12-1·82) CT (1·04-1·33), PET (1·00-1·58) and PET-CT (1·27-1·45). However, the modern imaging techniques detected fewer lesions in the skull and ribs. In a direct comparison CT and MRI performed equally with respect to detection rate and sensitivity. This systematic review supports the International Myeloma Working Group guidelines, which recommend that WBCT can replace WBXR. In our opinion, the equal performance of MRI also indicates that it is a valuable alternative. As lesions of the skull and ribs are underdiagnosed by modern imaging techniques we advise additional X-rays of these regions. The consequences of this approach are discussed.

FDG-PET in the evaluation of myeloma in 2012

Multiple myeloma (MM) is a malignant haematological disease characterised by clonal proliferation of malignant plasma cells in the bone marrow. MM is expressed by diffuse infiltration of the bone marrow, focal bone lesions and extra-medullary lesions. Conventional staging follows the Salmon and Durie classification, which was recently revised (Salmon and Durie plus) to include MRI and FDG-PET examinations. FDG-PET is being evaluated for initial staging and therapeutic monitoring and its place still needs to be validated, particularly in comparison with MRI of the pelvis and spine, the reference examination for diagnosis, which is systematically combined with X-rays of the skeleton. Certain recent data in the literature suggest that FDG-PET provides better staging of the disease at the time of diagnosis than MRI, and that the examination has considerable prognostic value when it normalises after the initial courses of chemotherapy and at the end of treatment. As for the evaluation of lymphomas, the interpretation criteria should be standardised.

Trends and outcomes of modern staging of solitary plasmacytoma of bone

Over the years, the definition of solitary plasmacytoma of bone (SPB) has shifted in part due to more modern testing capabilities. We hypothesized that outcomes data based on antiquated testing would not reflect outcomes using modern staging. To address both how widely applied adequate diagnostic staging is and what the progression rates of SPB as defined with state-of-the-art staging are, we performed a retrospective chart review of those patients with a diagnosis of SPB seen at our institution over the past decade. Two groups were studied: all patients with SPB (n = 127); and those patients referred to our institution for an indication other than progression (n = 91). The median PFS for those two groups were 26 months and 42 months, respectively. At baseline, only a minority of patients had state-of-the-art staging. The 5 patients with both modern imaging and a negative bone marrow had a 21 month PFS of 100%. Patients with plasmacytoma plus, one plasmacytoma but bone marrow consistent with monoclonal gammopathy of undetermined significance, fare worse than true SPB. The use of modern testing is imperative to characterize a patient's risk for progression. PET/CT plays an important role in the diagnostic work-up.