Incidence, characteristics, and outcome of solitary plasmacytoma and plasma cell leukemia. Population-based data from the Swedish Myeloma Register

Solitary Bone Plasmacytoma of the Skull Base With an Unusual Presentation

Solitary bone plasmacytoma (SBP) is a rare hematological malignancy that usually occurs in the spine and rarely in the skull. It rarely presents in the skull base, but presenting symptoms are associated with cranial nerve involvement depending on the site of the disease. We present the case of a 61-year-old man with an unusual presentation of hoarseness secondary to vocal fold palsy. Imaging showed a large bony lesion in the temporo-occipital region with involvement of the jugular foramen. Further detailed diagnostic procedures confirmed SBP of the skull base. Radiotherapy was given with an uneventful recovery of vocal fold function. Skull base plasmacytoma can be considered as a differential diagnosis of causes of unilateral vocal fold palsy. Early therapeutic management may improve vocal fold function.

Positron Emission Tomography/Computed Tomography Transformation of Oncology: Multiple Myeloma

This article provides a comprehensive review of the role of 2-deoxy-2-[18F]fluoro-d-glucose (18F FDG) positron emission tomography/computed tomography (PET/CT) in multiple myeloma (MM) and related plasma cell disorders. MM is a hematologic malignancy characterized by the neoplastic proliferation of plasma cells. 18F FDG PET/CT integrates metabolic and anatomic information, allowing for accurate localization of metabolically active disease. The article discusses the use of 18F FDG PET/CT in initial diagnosis, staging, prognostication, and assessing treatment response. Additionally, it provides valuable insights into the novel imaging targets including chemokine receptor C-X-C motif 4 and CD38.

International Consensus Statement on Allergy and Rhinology: Sinonasal Tumors

BACKGROUND

Sinonasal neoplasms, whether benign and malignant, pose a significant challenge to clinicians and represent a model area for multidisciplinary collaboration in order to optimize patient care. The International Consensus Statement on Allergy and Rhinology: Sinonasal Tumors (ICSNT) aims to summarize the best available evidence and presents 48 thematic and histopathology-based topics spanning the field.

METHODS

In accordance with prior International Consensus Statement on Allergy and Rhinology documents, ICSNT assigned each topic as an Evidence-Based Review with Recommendations, Evidence-Based Review, and Literature Review based on the level of evidence. An international group of multidisciplinary author teams were assembled for the topic reviews using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses format, and completed sections underwent a thorough and iterative consensus-building process. The final document underwent rigorous synthesis and review prior to publication.

RESULTS

The ICSNT document consists of four major sections: general principles, benign neoplasms and lesions, malignant neoplasms, and quality of life and surveillance. It covers 48 conceptual and/or histopathology-based topics relevant to sinonasal neoplasms and masses. Topics with a high level of evidence provided specific recommendations, while other areas summarized the current state of evidence. A final section highlights research opportunities and future directions, contributing to advancing knowledge and community intervention.

CONCLUSION

As an embodiment of the multidisciplinary and collaborative model of care in sinonasal neoplasms and masses, ICSNT was designed as a comprehensive, international, and multidisciplinary collaborative endeavor. Its primary objective is to summarize the existing evidence in the field of sinonasal neoplasms and masses.

Epidemiology and survival of primary extraosseous plasmacytoma: insights from a population-based study with a 20-year follow-up

Primary extraosseous plasmacytoma (PEP) is a rare and localized form of plasmacytoma that is not well understood. This study aimed to investigate the clinical features and prognostic factors associated with PEP. Using the Surveillance, Epidemiology, and End Results (SEER) database, a total of 1044 patients diagnosed with PEP between 2000 and 2019 were identified. The average age was 60.3 ± 15.2 years, with 64.3% being male (male: female = 1.8:1) and 53.8% being over 60-year old. The survival outcome of patients with PEP depends on several factors including age, race, marital status, and treatment options such as chemotherapy, radiotherapy, and surgery, which were also identified as independent predictors of overall survival for PEP. Patients who were younger, Asian or Pacific Islander, American Indian or Native American, and received radiotherapy or surgery had a more favorable prognosis, while those who underwent chemotherapy had poorer outcomes.

Imaging of the Craniocervical Junction: A Pictorial Review

The craniocervical junction (CCJ) is a complex anatomical structure comprising the occiput, the atlas, and the axis. The CCJ plays an important role in maintaining stability, providing protection, and supporting neurovascular structures. The CCJ can be affected by a wide range of congenital variants and traumatic, degenerative, inflammatory, and tumoral pathologies. This pictorial review the normal anatomy of the CCJ and presents the most common anatomical variants and pathologic conditions affecting the CCJ.

Imaging of Castleman Disease

Castleman disease (CD) is a group of rare and complex lymphoproliferative disorders that can manifest in two general forms: unicentric CD (UCD) and multicentric CD (MCD). These two forms differ in clinical manifestation, imaging appearances, treatment options, and prognosis. UCD typically manifests as a solitary enlarging mass that is discovered incidentally or after development of compression-type symptoms. MCD usually manifests acutely with systemic symptoms including fever and weight loss. As a whole, CD involves lymph nodes throughout the chest, neck, abdomen, pelvis, and axilla and can have a wide variety of imaging appearances. Most commonly, lymph nodes or masses in UCD occur in the chest, classically with well-defined borders, hyperenhancement, and possible characteristic patterns of calcification and/or feeding vessels. Lymph nodes affected by MCD, while also hyperenhancing, tend to involve multiple nodal chains and manifest alongside anasarca or hepatosplenomegaly. The polyneuropathy, organomegaly, endocrinopathy, monoclonal plasma cell disorder, and skin changes (POEMS) subtype of MCD may demonstrate lytic or sclerotic osseous lesions in addition to features typical of MCD. Since a diagnosis of CD based solely on imaging findings is often not possible, pathologic confirmation with core needle biopsy and/or surgical excision is necessary. Nevertheless, imaging plays a crucial role in supporting the diagnosis of CD, guiding appropriate regions for biopsy, and excluding other potential causes or mimics of disease. CT is frequently the initial imaging technique used in evaluating potential CD. MRI and PET play important roles in thoroughly evaluating the disease and determining its extent, especially the MCD form. Complete surgical excision is typically curative for UCD. MCD usually requires systemic therapy. ^©RSNA, 2023 Quiz questions for this article are available in the supplemental material.

Solitary Extramedullary Plasmacytoma With Development of T-cell Anaplastic Large-Cell Lymphoma: A Rare Case Report and Literature Review

Solitary extramedullary plasmacytomas are an exceedingly rare form of malignant neoplasms characterized by a single localized mass located in any soft tissue that consists of abnormal plasma cells. This type of tumor is characterized by the absence of plasmacytosis on bone marrow biopsy, the absence of other lesions on imaging, and no clinical signs of multiple myeloma. They usually present with mass effect, so the clinical picture varies based on the location of the tumor. In cases where the tumor is located in the gastrointestinal tract, patients may experience abdominal pain, small bowel obstruction, or gastrointestinal bleeding. The diagnostic process typically involves imaging to identify the tumor and its location, followed by a biopsy of the lesion with subsequent immunohistochemical analysis, as well as fluorescence in situ hybridization, and finally, bone marrow biopsy. Treatment options vary depending on the tumor's location and may include radiation therapy, surgical resection, and chemotherapy. Currently, radiation therapy is the preferred first-line treatment, with the best outcomes reported in the literature. Surgery is also frequently used and is often followed by radiation therapy. While chemotherapy has not been shown to have significant benefits, the available data is insufficient, and further studies are required to make better conclusions. Disease progression is often associated with transformation to multiple myeloma, but due to the rarity of the disease, data is limited, and it remains unclear if other forms of progression exist.   We report a case of a 63-year-old male who presented to the hospital with symptoms of abdominal pain, nausea, and vomiting. A computed tomography scan revealed a mass causing bowel obstruction, which was subsequently resected and evaluated by pathology. The final diagnosis was determined to be a solitary extramedullary plasmacytoma. Since the margins of the resected mass were clear, the patient was managed with solely clinical observation. Approximately eight months later, the patient was diagnosed with T-cell anaplastic large-cell lymphoma, ultimately leading to his passing 15 months after the initial diagnosis of solitary extramedullary plasmacytoma. We present this case to increase awareness of the rare condition of solitary extramedullary plasmacytoma and to highlight the potential association with T-cell anaplastic large-cell lymphomas, as demonstrated in this patient's case. Given the possibility of malignant transformation, close monitoring is warranted in similar cases.

More Than 2% of Circulating Tumor Plasma Cells Defines Plasma Cell Leukemia-Like Multiple Myeloma

PURPOSE

Primary plasma cell leukemia (PCL) is the most aggressive monoclonal gammopathy. It was formerly characterized by ≥ 20% circulating plasma cells (CTCs) until 2021, when this threshold was decreased to ≥ 5%. We hypothesized that primary PCL is not a separate clinical entity, but rather that it represents ultra-high-risk multiple myeloma (MM) characterized by elevated CTC levels.

METHODS

We assessed the levels of CTCs by multiparameter flow cytometry in 395 patients with newly diagnosed transplant-ineligible MM to establish a cutoff for CTCs that identifies the patients with ultra-high-risk PCL-like MM. We tested the cutoff on 185 transplant-eligible patients with MM and further validated on an independent cohort of 280 transplant-ineligible patients treated in the GEM-CLARIDEX trial. The largest published real-world cohort of patients with primary PCL was used for comparison of survival. Finally, we challenged the current 5% threshold for primary PCL diagnosis.

RESULTS

Newly diagnosed transplant-ineligible patients with MM with 2%-20% CTCs had significantly shorter progression-free survival (3.1 v 15.6 months; P < .001) and overall survival (14.6 v 33.6 months; P = .023) than patients with < 2%. The 2% cutoff proved to be applicable also in transplant-eligible patients with MM and was successfully validated on an independent cohort of patients from the GEM-CLARIDEX trial. Most importantly, patients with 2%-20% CTCs had comparable dismal outcomes with primary PCL. Moreover, after revealing a low mean difference between flow cytometric and morphologic evaluation of CTCs, we showed that patients with 2%-5% CTCs have similar outcomes as those with 5%-20% CTCs.

CONCLUSION

Our study uncovers that ≥ 2% CTCs is a biomarker of hidden primary PCL and supports the assessment of CTCs by flow cytometry during the diagnostic workup of MM.

Plasma cell neoplasms and related entities-evolution in diagnosis and classification

Plasma cell neoplasms including multiple myeloma (MM) and related terminally differentiated B-cell neoplasms are characterized by secretion of monoclonal immunoglobulin and stepwise development from a preneoplastic clonal B and/or plasma cell proliferation called monoclonal gammopathy of undetermined significance (MGUS). Diagnosis of these disorders requires integration of clinical, laboratory, and morphological features. While their classification mostly remains unchanged compared to the revised 2016 WHO classification and the 2014 International Myeloma Working Group consensus, some changes in criteria and terminology were proposed in the 2022 International Consensus Classification (ICC) of mature lymphoid neoplasms. MGUS of IgM type is now divided into IgM MGUS of plasma cell type, precursor to the rare IgM MM and characterized by MM-type cytogenetics, lack of clonal B-cells and absence of MYD88 mutation, and IgM MGUS, NOS including the remaining cases. Primary cold agglutinin disease is recognized as a new entity. MM is now formally subdivided into cytogenetic groups, recognizing the importance of genetics for clinical features and prognosis. MM with recurrent genetic abnormalities includes MM with CCND family translocations, MM with MAF family translocations, MM with NSD2 translocation, and MM with hyperdiploidy, with the remaining cases classified as MM, NOS. For diagnosis of localized plasma cell tumors, solitary plasmacytoma of bone, and primary extraosseous plasmacytoma, the importance of excluding minimal bone marrow infiltration by flow cytometry is emphasized. Primary systemic amyloidosis is renamed immunoglobulin light chain amyloidosis (AL), and a localized AL amyloidosis is recognized as a distinct entity. This review summarizes the updates on plasma cell neoplasms and related entities proposed in the 2022 ICC. KEY POINTS: • Lymphoplasmacytic lymphoma can be diagnosed with lymphoplasmacytic aggregates in trephine biopsies < 10% of cellularity and evidence of clonal B-cells and plasma cells. • IgM MGUS is subdivided into a plasma cell type and a not otherwise specified (NOS) type. • Primary cold agglutinin disease is recognized as a new entity. • The term "multiple myeloma" replaces the term "plasma cell myeloma" used in the 2016 WHO classification. • Multiple myeloma is subdivided into 4 mutually exclusive cytogenetic groups and MM NOS. • Minimal bone marrow infiltration detected by flow cytometry is of major prognostic importance for solitary plasmacytoma of bone and to a lesser extent for primary extraosseous plasmacytoma. • Localized IG light chain amyloidosis is recognized as a separate entity, distinct from systemic immunoglobulin light chain (AL) amyloidosis.

A Case of Synchronous Multiple Primary Malignancies Involving Multiple Myeloma and Pharyngeal Plasmacytoma in an Elderly Male: A Case Report and Review of the Literature

Monoclonal plasma cells form the solitary neoplasm known as solitary plasmacytoma. Isolated extramedullary plasmacytoma is less common than solitary bone plasmacytoma. An elderly male presented with coughing blood and was diagnosed with pharyngeal plasmacytoma with synchronous multiple myeloma. Herein, we present this challengingly rare case to increase awareness of this unusual entity.

Radiographic Response of Solitary Plasmacytomas After Conformal Radiotherapy May Be Delayed: Outcomes in the 3D Era

OBJECTIVE

Although recurrence rates after radiotherapy for solitary plasmacytoma (SP) are well established, little is known about how SP responds radiographically, as most historical patients were treated in the 2D era. We evaluated the response to radiotherapy among SP patients staged and treated with 3D techniques, including proton therapy, which has not yet been previously reported.

METHODS AND MATERIALS

Between 2007 and 2021, 15 SP patients (4 extramedullary, 11 bone) staged with 3D imaging and bone marrow evaluation were consecutively treated with definitive radiotherapy. The best response was categorized in 9 evaluable patients according to response evaluation criteria in solid tumors (RECIST) and positron emission tomography response criteria in solid tumors (PERCIST).

RESULTS

With a median follow-up of 34 months, 4 patients relapsed. The median time to the best response was ~2 years (26.6 mo RECIST, 25.4 mo PERCIST). Response rates differed based on response assessment criteria. PERCIST was associated with higher rates of complete (85.7%) or partial response (14.3%) compared with RECIST (16.7% complete, 33.3% partial). Two-year and 4-year PFS for extramedullary SP were 100% and 75%, compared with 91% and 55% for bone ( P =0.75). Patients treated with proton therapy (n=5) did not appear to have different patterns of relapse (1 marginal, 1 distant) compared with those treated with photons or electrons (n=10; 2 distant).

CONCLUSIONS

More conformal dose distribution with proton therapy does not appear to alter patterns of recurrence. Although response rates differ based on criteria by both RECIST and PERCIST assessments, the radiographic response may be slow and requires validation in other cohorts.

The International Consensus Classification of Mature Lymphoid Neoplasms: a report from the Clinical Advisory Committee

Since the publication of the Revised European-American Classification of Lymphoid Neoplasms in 1994, subsequent updates of the classification of lymphoid neoplasms have been generated through iterative international efforts to achieve broad consensus among hematopathologists, geneticists, molecular scientists, and clinicians. Significant progress has recently been made in the characterization of malignancies of the immune system, with many new insights provided by genomic studies. They have led to this proposal. We have followed the same process that was successfully used for the third and fourth editions of the World Health Organization Classification of Hematologic Neoplasms. The definition, recommended studies, and criteria for the diagnosis of many entities have been extensively refined. Some categories considered provisional have now been upgraded to definite entities. Terminology for some diseases has been revised to adapt nomenclature to the current knowledge of their biology, but these modifications have been restricted to well-justified situations. Major findings from recent genomic studies have impacted the conceptual framework and diagnostic criteria for many disease entities. These changes will have an impact on optimal clinical management. The conclusions of this work are summarized in this report as the proposed International Consensus Classification of mature lymphoid, histiocytic, and dendritic cell tumors.

18F-FDG Versus Non-FDG PET Tracers in Multiple Myeloma

Multiple myeloma (MM) accounts for 0.9% of cancer diagnoses, and incidence and mortality rate have increased in previous years. 18F-fluorodeoxyglucose (FDG) PET-computed tomography (CT) is an established modality for MM evaluation. MR imaging is helpful where 18F-FDG PET-CT is lacking. To standardize PET reporting, methods like Italian Myeloma Criteria for PET Use and Deauville criteria have been studied. Tracers like 11C-acetate and 11C-choline/18F-fluoromethylcholine (FCH) have shown higher sensitivity and detected more focal lesions and diffuse involvement than 18F-FDG PET-CT. 18F-FCH showed higher maximum standardized uptake value than 18FDG. 11C-methionine appears to be the best radiopharmaceutical, apart from 18F-FDG, for evaluating MM.

Regional differences in treatment and outcome for myeloma patients in Sweden: A population based Swedish myeloma register study

BACKGROUND

We wanted to evaluate if health care for multiple myeloma (MM) patients is equal in different regions of Sweden.

AIM

To study differences in survival for MM depending on health care region and early use of modern treatment.

METHODS AND RESULTS

Data from the Swedish Myeloma Register from patients diagnosed between 2008 and 2017 was used. Cohorts were defined by the six healthcare regions (labeled A-F) in Sweden and modern initial treatment was defined as including certain drug combinations. To adjust for time to treatment bias, survival analyses were performed also for patients alive 6 months after diagnosis. In all treated MM patients (n = 5326), we observed a superior overall survival (OS) for region A compared to all other regions (p < .01 for all respectively). After adjusting for time to treatment there was also a superior survival in the region with highest use of modern initial treatment (region A) compared to the regions defined in the study as having intermediate and low use (p < .01 for both). In patients receiving autologous stem cell transplantation (ASCT) a superior survival was observed for region A compared to all regions besides region B. Similar results were seen when adjusting for a time to treatment bias. In patients not receiving ASCT, 75 years or older and adjusted for time to treatment bias, a difference was noted only between region A and E (log rank p = .04, HR 1.2, CI 1.00-1.44, p = .06). In multivariate analyses including age, international staging system stage and time period of diagnosis, differences in survival remained for patients receiving ASCT between region A versus C, D, E and F (p = .01, p < .01, p < .01, p = .03).

CONCLUSION

We observed a superior survival in region A for patients receiving ASCT. Explanations may be higher usage of modern initial treatment or regional residual confounding. For patients not receiving ASCT, 75 years or older, differences in survival could be adjusted for.

Radiotherapy alleviates spinal cord compression caused by solitary bone plasmacytoma: A case report

INTRODUCTION AND IMPORTANCE

Solitary bone plasmacytoma (SBP) is a hematopoietic malignancy occurring in bone tissue, which often causes bone destruction at the site of the lesion. When the lesion occurs in the spine and causes spinal stenosis and compression of the spinal cord, surgery is performed as an adjuvant treatment before radiotherapy.

CASE PRESENTATION

A 36-year-old patient suffered from neck, shoulder and upper limbs pain for 3 weeks and the symptom worsened for 3 days after exercise. CT and MRI examination of the neck after emergency admission revealed C5 vertebral pathological fracture with associated spinal stenosis and spinal cord compression. PET-CT indicated a hypermetabolic soft tissue mass in the C5-6 vertebral body. Granulomatous lesions (tuberculosis) were considered, but neoplastic lesions were not ruled out. The primary diagnosis was cervical fracture caused by tuberculosis. Finally, a needle biopsy was performed at the lesion site and a diagnosis of SBP was made. Radiotherapy was immediately followed and the spinal cord compression was relieved a month later. After 6 months of follow-up, she is now in stable condition with no neck pain or neurological impairment.

CONCLUSION

For patients with SPB resulting in pathological fracture of the cervical vertebra with spinal stenosis and compression of the spinal cord, forgoing surgery and undergoing radiation therapy alone may be an option.

Multiple myeloma: a review of atypical imaging features and other distinct plasma cell disorders that demonstrate similar imaging features

Multiple osteolytic lesions are a well-recognized and typical imaging feature of multiple myeloma as well as several other plasma cell disorders. Given the high volume of imaging studies obtained of multiple myeloma patients, radiologists will likely encounter a subset of multiple myeloma patients with less common or "atypical" findings during their practice. These atypical findings include osteosclerotic lesions, extramedullary lesions, and amyloid deposition. Similar imaging findings that are considered atypical for multiple myeloma can also be detected in other plasma cell disorders that are distinct from multiple myeloma. For instance, POEMS syndrome is a distinct plasma cell disorder from multiple myeloma, but also can present with osteosclerotic lesions. This article reviews the atypical findings associated with multiple myeloma and also reviews other plasma cell disorders that can have a similar spectrum of imaging findings. Special attention is paid to the musculoskeletal imaging findings.

Breast Plasmacytoma as Extra-Medullary Lesion of Multiple Myeloma: A Case Report

Breast plasmacytoma is relatively uncommon in which most of the recorded cases were related to disseminated multiple myeloma. However, many of these cases tend to be misdiagnosed with other breast lesions such as breast carcinoma. This article presents a case study on a Libyan female patient around the age of 55 who has a single breast lump, which was first diagnosed to be a malignant lesion. All the results of immunostaining for cytokeratins, GATA3, estrogen receptor, progesterone receptor, HER2, and E-cadherin were negative; hence, the possibility of a breast carcinoma was not considered. However, plasma cell tumors were indicated by the presence of CD138, MUM1, and kappa-light chain markers. In addition, the patient had multiple osteolytic bone lesions, plasma cell infiltration, a monoclonal gammopathy, and signs of renal failure, which considered to be an indication to an extra-medullary breast plasmacytoma secondary to advanced multiple myeloma. This case study emphasizes the necessity of complete histopathological and imaging evolution for proper diagnosis of breast plasmacytoma.

Whole-body magnetic resonance imaging (WBMRI) versus whole-body computed tomography (WBCT) for myeloma imaging and staging

Myeloma-associated bone disease (MBD) develops in about 80-90% of patients and severely affects their quality of life, as it accounts for the majority of mortality and morbidity. Imaging in multiple myeloma (MM) and MBD is of utmost importance in order to detect bone and bone marrow lesions as well as extraosseous soft-tissue masses and complications before the initiation of treatment. It is required for determination of the stage of disease and aids in the assessment of treatment response. Whole-body low-dose computed tomography (WBLDCT) is the key modality to establish the initial diagnosis of MM and is now recommended as reference standard procedure for the detection of lytic destruction in MBD. In contrast, whole-body magnetic resonance imaging (WBMRI) has higher sensitivity for the detection of focal and diffuse plasma cell infiltration patterns of the bone marrow and identifies them prior to osteolytic destruction. It is recommended for the evaluation of spinal and vertebral lesions, while functional, diffusion-weighted MRI (DWI-MRI) is a promising tool for the assessment of treatment response. This review addresses the current improvements and limitations of WBCT and WBMRI for diagnosis and staging in MM, underlining the fact that both modalities offer complementary information. It further summarizes the corresponding radiological findings and novel technological aspects of both modalities.

Outcome data from >10 000 multiple myeloma patients in the Danish and Swedish national registries

OBJECTIVE

We describe real-world evidence (RWE) from the nationwide Swedish and Danish registries that provide important information on incidence and outcome in multiple myeloma (MM).

METHOD

First line treatment data on more than 10.000 MM patients from Denmark and Sweden between 2005-2018 are presented. Key results from research conducted within the Swedish and Danish myeloma registries are summarized, describing subgroups of patients with comorbidity, myeloma complications, and early relapse.

RESULTS

We show that national guidelines, generated on results from randomized clinical trials (RCTs) are rapidly implemented and improve overall survival (OS). We find that both the incidence of MM and the median age at diagnosis is higher in national registries compared to results from referral centres, indicating a more complete coverage. This highlights the need of validation of prognostic scoring systems and indices in e.g., SMM and high-risk MM in a real- world-population. We show that these subgroups are unlikely to be captured in RCTs with narrow inclusion and exclusion criteria, that they have worse survival, and are in need of new treatment approaches.

CONCLUSION

National registries that include all MM patients are an important source of knowledge on epidemiology, treatment and outcome with implications for the planning of MM care. Despite the introduction of new and better treatments, rapidly implemented in our countries, our registries uncover subgroups of patients that still have inferior outcome. Our RWE can help to identify important research questions to be studied in further clinical trials also in patients currently not included in RCTs.

Solitary osseous plasmacytomas in dogs: 13 cases (2004-2019)

Objectives

To further characterise solitary osseous plasmacytoma in dogs, an extremely rare disease. To describe diagnosis, disease progression and treatment outcomes in dogs with solitary osseous plasmacytoma.

Materials and Methods

Retrospective review of dogs with solitary osseous plasmacytomas that were diagnosed and treated at a single institution from 2005 to 2019. Kaplan–Meier single group survival analysis was used to estimate median survival time and progression‐free interval.

Results

Thirteen dogs met the inclusion criteria for the study, and of those, 11 were treated. The median age at diagnosis was 8 years (range 4 to 11). Most solitary osseous plasmacytomas occurred in the vertebrae (n=8). Other sites included the maxilla (n=2), the mandible (n=1), the tibia (n=1) and the carpus (n=1). The median survival time for all dogs with solitary osseous plasmacytoma was 912 days (range 5 to 2179), and the progression‐free interval for treated dogs was 310 days (range 22 to 2179). Most dogs were treated with radiation therapy (n=10) with nine of 10 receiving a definitive, daily fractionated protocol and with five of ten having had neoadjuvant surgery. Seven dogs received chemotherapy, which was initiated after progressive disease in five dogs. The median survival time for dogs that completed radiation therapy (n=9) was 1166 days (range 545 to 2179). While five dogs developed lesions at other sites, no dogs progressed to multiple myeloma.

Clinical Significance

Canine solitary osseous plasmacytomas can be managed long term with appropriate local therapy. This observation reflects the biologic behaviour observed in humans.

[Prevalence investigation of plasma cell leukemia in China: a calculation based on national urban medical insurance in 2016]

目的

分析我国城市人口中浆细胞白血病（PCL）的流行病学特征，并测算2016年PCL患病率。

方法

利用我国23个省2016年1月1日至2016年12月31日的城镇基本医疗保险数据进行测算。利用医疗保险数据中的疾病诊断名称和疾病诊断编码识别PCL患者。按性别、地区和年龄进行亚组分析，并通过敏感性分析考察结果的稳健性。基于我国2010年全国人口普查数据计算按年龄调整的标准化患病率。

结果

2016年我国城市人口中PCL患病率为0.11/10万（95％CI 0.05～0.19），其中男性和女性患病率分别为0.12/10万（95％CI 0.06～0.21），0.10/10万（95％CI 0.04～0.19）。PCL的患病率在70～79岁时达高峰。敏感性分析显示本研究结果具有稳健性。根据我国2010年全国人口普查数据所得的标化患病率为0.12/10万（95％CI 0.11～0.13）。

结论

本研究首次利用全国城镇医疗保险数据测算我国PCL的患病率，为PCL相关研究和政策制定提供依据。

18F-FDG PET/CT in the Evaluation of Solitary Extramedullary Plasmacytoma: A Case Series

The role of fluorine-18-fluorodeoxyglucose positron emission tomography/ computed tomography (¹⁸F-FDG PET/CT) in patients with multiple myeloma (MM) and other plasma cell disorders is well-known. Solitary plasmacytoma (SP), an extremely rare form within this entity accounting for approximately 4% of plasma cell malignancies, can be classified as solitary bone plasmacytoma (SBP) or solitary extramedullary plasmacytoma (SEMP). Extramedullary plasmacytoma (EMP) is a rare neoplasm characterized by the monoclonal proliferation of plasma cells outside the bone marrow. Breast and craniocerebral regions are the uncommon sites of the presentations of EMP, rarely reported in the literature. The most frequent site of presentation is the upper airways. The EMPs have similar pathogenesis as MM; however, they differ in management as they are radiosensitive in nature, and radiotherapy is the preferred treatment modality. As SEMP has a better prognosis than SPB with a lower conversion rate to MM, accurate staging is essential to plan for the treatment. The ¹⁸F-FDG PET/CT has higher sensitivity for the evaluation of treatment response. In the present case series, it was aimed to depict the role of ¹⁸F-FDG PET/CT in newly diagnosed SEMP with different sites of origin to exclude further lesions leading to changes in the treatment plan and treatment response assessment.

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

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

Extramedullary Plasmacytoma: Long-Term Clinical Outcomes in a Single-Center in China and Literature Review

The aim is to analyze the clinical outcomes of patients with extramedullary plasmacytoma (EMP) and review the characteristics of this disease. We retrospectively reviewed the clinical data of a cohort of 22 patients diagnosed with EMP between 1983 and 2017. Baseline characteristics and progression data were collected to calculate the incidence of progression to multiple myeloma (MM) and to analyze survival rates and outcomes. Previous major cohort studies were reviewed and compared with this study. Extramedullary plasmacytomas were located in the head and neck in 17 (77%) of the 22 patients. The median time between onset and diagnosis was 7 months, and the median age at diagnosis was 52.5 years (range 15-72 years). Extramedullary plasmacytoma occurred more frequently in men with an approximate ratio of 2.1:1. The majority of patients underwent surgery (13/22, 59.1%) and half received radiation (11/22, 50%). A small proportion of patients received chemotherapy (2/22, 9.1%). There was a median follow-up time of 98.5 months. The 5-year overall survival, progression-free survival, and MM-free survival rates were 84.2%, 67.3% and 75.9%, respectively. Complete resection without major functional damage is a promising option that can favorably improve prognosis in patients with resectable disease. Patients with regional lymph node metastasis or positive immunoelectrophoresis results require more aggressive treatment and may have poorer prognosis.

[Prevalence investigation of solitary plasmacytoma in China: A calculation based on national urban medical insurance in 2016]

目的

分析我国孤立性浆细胞瘤患者分布特征并测算2016年患病率。

方法

基于2016年1月1日至12月31日我国21个省城镇职工和城镇居民医疗保险数据开展研究。通过疾病诊断名称、疾病诊断编码识别孤立性浆细胞瘤患者。根据性别、地区和年龄进行亚组分析，并进行敏感性分析以考察结果的稳健性。基于我国2010年全国人口普查数据、欧洲2013年标准人口数据、美国2010年人口数据以及澳大利亚2011年人口数据计算按年龄调整的标化患病率。

结果

2016年我国孤立性浆细胞瘤患病率为1.18/10万（95%CI 1.06~1.31），其中男性患病率为1.26/10万（95%CI 1.10~1.43），女性患病率为1.10/10万（95%CI 0.93~1.29）。基于我国2010年全国人口普查数据所得标化患病率为0.85/10万（95%CI 0.82~0.88）。

结论

本研究利用全国城镇医疗保险数据测算我国孤立性浆细胞瘤的患病率，为孤立性浆细胞瘤相关医疗政策制定以及基础研究提供线索。

Solitary Plasmacytoma: a Review of Diagnosis and Management

PURPOSE OF REVIEW

Solitary plasmacytoma is a rare plasma cell dyscrasia, classified as solitary bone plasmacytoma or solitary extramedullary plasmacytoma. These entities are diagnosed by demonstrating infiltration of a monoclonal plasma cell population in a single bone lesion or presence of plasma cells involving a soft tissue mass, respectively. Both diseases represent a single localized process without significant plasma cell infiltration into the bone marrow or evidence of end organ damage. Clinically, it is important to classify plasmacytoma as having completely undetectable bone marrow involvement versus minimal marrow involvement. Here, we discuss the diagnosis, management, and prognosis of solitary plasmacytoma.

RECENT FINDINGS

There have been numerous therapeutic advances in the treatment of multiple myeloma over the last few years. While the treatment paradigm for solitary plasmacytoma has not changed significantly over the years, progress has been made with regard to diagnostic tools available that can risk stratify disease, offer prognostic value, and discern solitary plasmacytoma from quiescent or asymptomatic myeloma at the time of diagnosis. Despite various studies investigating the use of systemic therapy or combined modality therapy for the treatment of plasmacytoma, radiation therapy remains the mainstay of therapy. Much of the recent advancement in the management of solitary plasmacytoma has been through the development of improved diagnostic techniques.

Multiple myeloma with dural mater involvement

Multiple myeloma is an incurable clonal B-cell malignancy which may present with neoplastic monoclonal plasma cells in either bone or soft tissues. Central nervous system (CNS) involvement such as dural myeloma or intraparenchymal infiltration, or with diffuse leptomeningeal involvement, is uncommon. Dural involvement of myeloma without parenchymal or leptomeningeal disease is an even rarer occurrence; therefore there are no established treatment guidelines for CNS myelomatosis. Here we reported a refractory MM patient progressed to dura mater involvement after the induction therapy but showed good response to lenalidomide treatment.

Revised diagnostic criteria for plasma cell leukemia: results of a Mayo Clinic study with comparison of outcomes to multiple myeloma

The current definition of plasma cell leukemia (PCL)- ≥ 20% circulating plasma cells (CPCs) on peripheral smear and plasma cell count ≥ 2 × 10⁹/L-may be too stringent. We reviewed outcomes of 176 multiple myeloma (MM) patients diagnosed between 1971 and 2016, and who had CPCs detectable at diagnosis, to determine whether a lower threshold could be used to diagnose PCL. Median overall survival (mOS) was 1.1 years (95% CI 0.8-1.4) and was similar between patients with < 5% (n = 54, mOS = 1.4 years [0.7-2.0]), 5-19% (n = 63, mOS = 1.1 years [0.7-1.4]), and ≥ 20% CPCs (n = 59, mOS = 1.1 years [0.7-1.5], p = 0.349). As survival was similar between those with 5-19% and ≥ 20% CPCs, we stratified patients by < 5% (mOS = 1.4 years [0.7-2.0]) and ≥ 5% CPCs (mOS = 1.1 years [0.8-1.4], p = 0.154). Outcomes of those with ≥ 5% CPCs were much poorer when compared with a cohort of MM patients diagnosed between 1971 and 2016, who did not have CPCs at diagnosis (n = 9724, mOS = 4.4 yrs [4.3-4.5], p < 0.001); survival was also lower in patients diagnosed after 2001 with ≥ 5% CPCs (n = 62, mOS = 1.4 years [0.8-2.5]) compared with patients with standard risk (n = 1326, mOS = 7.5 years [7.0-8.7]) and high-risk MM (n = 381, mOS = 4.3 years [3.5-4.9], p < 0.001). We therefore propose that the definition of PCL be revised to patients with ≥ 5% CPCs on peripheral blood smear, who otherwise meet diagnostic criteria for MM.

Anaplastic plasmacytoma: a rare tumor presenting as a pathological fracture in a younger adult

Solitary plasmacytoma is the rarest type of plasma cell neoplasm, and the anaplastic form is even more uncommon. Plasmacytoma most commonly originates in bone and predominantly affects older patients. We describe the case of a 35-year-old woman with solitary osseous anaplastic plasmacytoma that presented initially with a pathological fracture following minor trauma. The patient was immunocompetent and had no predisposing conditions for a plasma cell tumor. Left lower extremity radiographs revealed an oblique fracture of the distal femur, and CT imaging indicated a primary osseous lesion at the fracture site. MRI confirmed the diagnosis of pathological fracture. Initial surgical pathology of the lesion was concerning because it could have been an osteosarcoma. Further immunostaining demonstrated CD138 positivity and kappa light chain restriction, confirming the diagnosis of plasmacytoma. In addition, the presence of marked anaplastic cellular changes confirmed the anaplastic variant. Further workup showed no evidence of multiple myeloma. This case is unusual given the age and gender of the patient. Awareness of the anaplastic variant of plasmacytoma is important to avoid erroneous diagnoses.

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.