Plasmacytoma Research Articles

The genomic landscape of Vk*MYC myeloma highlights shared pathways of transformation between mice and humans

Multiple myeloma (MM) is a heterogeneous disease characterized by frequent MYC translocations. Sporadic MYC activation in the germinal center of genetically engineered Vk*MYC mice is sufficient to induce plasma cell tumors in which a variety of secondary mutations are spontaneously acquired and selected over time. Analysis of 119 Vk*MYC myeloma reveals recurrent copy number alterations, structural variations, chromothripsis, driver mutations, apolipoprotein B mRNA-editing enzyme, catalytic polypeptide (APOBEC) mutational activity, and a progressive decrease in immunoglobulin transcription that inversely correlates with proliferation. Moreover, we identify frequent insertional mutagenesis by endogenous retro-elements as a murine specific mechanism to activate NF-kB and IL6 signaling pathways shared with human MM. Despite the increased genomic complexity associated with progression, advanced tumors remain dependent on MYC. In summary, here we credential the Vk*MYC mouse as a unique resource to explore MM genomic evolution and describe a fully annotated collection of diverse and immortalized murine MM tumors.

CyberKnife stereotactic radiosurgery for extramedullary plasmacytoma in the external auditory canal: illustrative case.

Plasmacytoma, a rare plasma cell disorder, often presents as a solitary or multiple tumors within the bone marrow or soft tissues, typically associated with multiple myeloma. Extramedullary plasmacytomas (EMPs), particularly those located in the external auditory canal (EAC), are exceedingly rare and pose significant treatment challenges given their location, anatomical complexity, and high risk of recurrence. The authors report the case of a 72-year-old male with a history of multiple myeloma, presenting with recurrent left EAC plasmacytoma. After initial conventional radiotherapy for the lesion, a recurrence was documented in 7 years. The patient subsequently underwent stereotactic radiosurgery, which proved successful, leading to complete resolution of the lesion without any long-term adverse effects or radiation-related complications over a 45-month period. This case is a unique instance of utilizing stereotactic radiosurgery for recurrent EMP in the EAC, highlighting its potential as an effective approach in managing complex plasmacytomas.

Detection of clonal plasma cells in POEMS syndrome using multiparameter flow cytometry

POEMS syndrome (polyneuropathy, organomegaly, endocrinopathy, monoclonal protein [M-protein], and skin changes) is a rare systemic disorder characterized by various symptoms caused by underlying plasma cell (PC) dyscrasia. Detection of monoclonal PCs is mandatory for the diagnosis of POEMS syndrome; however, the usefulness of EuroFlow-based next-generation flow cytometry (EuroFlow-NGF) in POEMS syndrome for detecting monoclonal PCs in bone marrow (BM) and the gating strategy suitable for flow cytometry study of POEMS syndrome remain unknown. We employed EuroFlow-NGF-based single-tube eight-color multiparameter flow cytometry (MM-flow) and established a new gating strategy (POEMS-flow) to detect the monoclonal PCs in POEMS syndrome, gating CD38 broadly from dim to bright and CD45 narrowly from negative to dim compared to MM-flow. MM-flow detected monoclonal PCs in 9/25 (36.0%) cases, including 2/2 immunofixation electrophoresis (IFE)-negative cases (100%). However, POEMS-flow detected monoclonal PCs in 18/25 cases (72.0%), including 2/2 IFE-negative cases (100%). POEMS-flow detected monoclonal PCs with immunophenotypes of CD19− in 17/18 (94.4%). In six cases where post-treatment samples were available, the size of the clones was significantly reduced after the treatment (P = 0.031). POEMS-flow can enhance the identification rate of monoclonal PCs in POEMS syndrome and become a valuable tool for the diagnosis of POEMS syndrome.

A young patient with cord compression diagnosed as a solitary sacral plasmacytoma: a case report

A young patient with cord compression diagnosed as a solitary sacral plasmacytoma: a case report

Patient perspectives on BCMA-targeted therapies for multiple myeloma: a survey conducted in a patient advocacy group.

Advances in multiple myeloma (MM) treatment have shifted the therapeutic landscape. Understanding patients' perspectives can assist physicians in helping patients make informed decisions. This study aimed to understand the patient decision-making process and gain insights into patient perspectives on B-cell maturation antigen (BCMA)-targeted therapies for MM. An 18-question survey was completed by patients with MM enrolled in HealthTree® Cure Hub, an online portal helping patients with plasma cell dyscrasias navigate their disease. From October 28, 2022, to January 12, 2023, 325 patients with MM participated in the survey. The mean age (standard deviation) of the respondents was 66 (8) years; 54% were female and 90% were White. Among 218 patients with complete clinical records in the database, the median (min, max) lines of therapy (LOT) was 2 (1,16). Among 61 (28%) patients who had received ≥4 LOTs, 55 (90%) were triple-class exposed. Of the 290 patients who responded to the question about openness to new therapies, 76 (26%) were open to trying a new therapy immediately and 125 (43%) wanted more information on safety and efficacy. Most respondents reported likely or very likely to try a BCMA CAR T-cell therapy (60%) or a bispecific antibody (74%) and some needed more information to decide (16% for CAR T-cell therapy and 13% for bispecific antibody). The most requested information included efficacy, side effects (SEs), eligibility, and administration process for both CAR T-cell and bispecific therapies. When 2 therapies with the same efficacy and duration of response were offered, 69% of respondents would prefer the therapy with a lower risk of severe SEs but requires continuous dosing with no treatment-free interval, and 31% preferred a therapy given once followed by a treatment-free interval but with a potentially higher risk of severe SEs. To receive an effective therapy, the top acceptable trade-offs included frequent monitoring of SEs and initiating a new therapy in a hospital setting, and the least acceptable compromise was caregiver burden. This study found a high level of openness in patients with MM to try BCMA-targeted therapies. Information on efficacy, safety, availability, and eligibility may assist patients on decision-making.

Immune escape of multiple myeloma cells results from low miR29b and the ensuing epigenetic silencing of proteasome genes

BackgroundActivation of CD28 on multiple myeloma (MM) plasma cells, by binding to CD80 and CD86 on dendritic cells, decreases proteasome subunit expression in the tumor cells and thereby helps them evade being killed by CD8+ T cells. Understanding how CD28 activation leads to proteasome subunit downregulation is needed to design new MM therapies.MethodsThis study investigates the molecular pathway downstream of CD28 activation, using an in vitro model consisting of myeloma cell lines stimulated with anti-CD28-coated beads.ResultsWe show that CD28 engagement on U266 and RPMI 8226 cells activates the PI3K/AKT pathway, reduces miR29b expression, increases the expression of DNA methyltransferase 3B (DNMT3B, a target of miR29b), and decreases immunoproteasome subunit expression. In vitro transfection of U266 and RPMI 8226 cells with a miR29b mimic downregulates the PI3K/AKT pathway and DNMT3B expression, restores proteasome subunit levels, and promotes myeloma cell killing by bone marrow CD8+ T cells from MM patients. Freshly purified bone marrow plasma cells (CD138+) from MM patients have lower miR29b and higher DNMT3B (mRNA and protein) than do cells from patients with monoclonal gammopathy of undetermined significance. Finally, in MM patients, high DNMT3B levels associate with shorter overall survival.ConclusionsAltogether, this study describes a novel molecular pathway in MM. This pathway starts from CD28 expressed on tumor plasma cells and, through the PI3K-miR29b-DNMT3B axis, leads to epigenetic silencing of immunoproteasome subunits, allowing MM plasma cells to elude immunosurveillance. This discovery has implications for the design of innovative miR29b-based therapies for MM.

Multifocal Extramedullary Plasmacytoma of the Thyroid With Cervical and Paratracheal Lymph Node Involvement and Progression to Multiple Myeloma

Multifocal Extramedullary Plasmacytoma of the Thyroid With Cervical and Paratracheal Lymph Node Involvement and Progression to Multiple Myeloma

Construction of immune-related gene pairs signature to predict the overall survival of multiple myeloma patients based on whole bone marrow gene expression profiling.

Multiple myeloma (MM) is a plasma cell dyscrasia that is characterized by the uncontrolled proliferation of malignant PCs in the bone marrow. Due to immunotherapy, attention has returned to the immune system in MM, and it appears necessary to identify biomarkers in this area. In this study, we created a prognostic model for MM using immune-related gene pairs (IRGPs), with the advantage that it is not affected by technical bias. After retrieving microarray data of MM patients, bioinformatics analyses like COX regression and least absolute shrinkage and selection operator (LASSO) were used to construct the signature. Then its prognostic value is assessed via time-dependent receiver operating characteristic (ROC) and the Kaplan-Meier (KM) analysis. We also used XCELL to examine the status of immune cell infiltration among MM patients. 6-IRGP signatures were developed and proved to predict MM prognosis with a P-value of 0.001 in the KM analysis. Moreover, the risk score was significantly associated with clinicopathological characteristics and was an independent prognostic factor. Of note, the combination of age and β2-microglobulin with risk score could improve the accuracy of determining patients' prognosis with the values of the area under the curve (AUC) of 0.73 in 5 years ROC curves. Our model was also associated with the distribution of immune cells. This novel signature, either alone or in combination with age and β2-microglobulin, showed a good prognostic predictive value and might be used to guide the management of MM patients in clinical practice.

Melan-A immunolabeling in canine extramedullary plasmacytomas.

Histologic diagnosis of less well-differentiated cases of canine extramedullary plasmacytomas (CEMPs) may require immunohistochemical confirmation to discriminate these tumors from other round cells tumors including lymphoma, cutaneous histiocytoma, and amelanotic melanomas. CEMPs are characterized by widespread immunoreactivity for multiple myeloma 1 (MUM1) antigen and λ light chains, while the melanocytic marker melan-A has been reported to yield negative results. Here, 33 randomly selected CEMPs, 20 melanocytomas, and 20 malignant melanomas were immunohistochemically tested for MUM1, melan-A, and PNL2. In addition, CEMPs were examined for PAX5, E-cadherin, CD3, CD18, CD20, S100, as well as λ and κ light chain immunoreactivity. All CEMPs were characterized by labeling for MUM1 and λ light chain, as well as variable immunopositivity for the remaining antibodies. Notably, 13 cases of CEMPs (39.4%) exhibited immunolabeling for melan-A. Melanocytic tumors immunolabeled for melan-A (40/40; 100%) and PNL2 (34/40; 85%). An unexpected cytoplasmic immunoreactivity for MUM1 was observed in 2 melanocytic tumors. Summarized, MUM1 or melan-A immunomarkers alone are not sufficient to differentiate between CEMPs and amelanotic melanomas and should be part of a larger immunopanel including λ light chain, CD20, and PNL2.

Pathway for Development and Validation of Multi-domain Endpoints for Amyloid Light Chain (AL) Amyloidosis.

Immunoglobin light chain (AL) amyloidosis is a rare disease in which a plasma cell dyscrasia leads to deposition of insoluble amyloid fibrils in multiple organs. To facilitate development of new therapies for this heterogenous disease, a public-private partnership was formed between the nonprofit Amyloidosis Research Consortium and the US Food and Drug Administration Center for Drug Evaluation and Research. In 2020, the Amyloidosis Forum launched an initiative to identify clinical trial endpoints and analytic strategies across affected organ systems and life impacts via specialized working groups. This review summarizes the proceedings of the Statistical Group and proposes a pathway for development and validation of multi-domain endpoints (MDEs) for potential use in AL amyloidosis clinical trials. Specifically, drawing on candidate domain-specific endpoints recommended by each organ-specific working group, different approaches to constructing MDEs were considered. Future studies were identified to assess the validity, meaningfulness and performance of MDEs through use of natural history and clinical trial data. Ultimately, for drug development, the context of use in a regulatory evaluation, the specific patient population, and the investigational therapeutic mechanism should drive selection of appropriate endpoints. MDEs for AL amyloidosis, once developed and validated, will provide important options for advancing patient-focused drug development in this multi-system disease.

Spontaneous regression of multiple solitary plasmacytoma harboring Epstein-Barr virus: a case report and literature review.

We report a rare case of spontaneous regression (SR) in an elderly untreated patient with multiple solitary plasmacytoma (MSP). Diagnosis of MSP was confirmed through surgical resection of the left nasal cavity mass and subsequent biopsy of the right humerus. The patient was considered ineligible for chemotherapy due to poor performance status. At 3-month post-diagnosis, the patient's condition worsened with deteriorating bone lesions and emergence of a new serum monoclonal protein. However, these clinical findings completely disappeared at 6months, and positron emission tomography-computed tomography at 1year confirmed complete metabolic remission. Notably, peripheral blood lymphocyte counts were inversely correlated with tumor progression and remission. Pathological re-evaluation of the initial biopsy specimens revealed programmed cell death protein 1 (PD-1) expression in tumor-infiltrating CD8+ T cells. In addition, tumor cells were infected with Epstein-Barr virus (EBV) but were negative for programmed cell death ligand 1 (PD-L1) expression, which is the most potent immune escape mechanism in tumor cells. While the mechanism underlying SR remains unclear, our findings suggest that host immune response as well as EBV infection may contribute to SR. Further studies are needed to elucidate the clinicopathologic mechanisms of tumor regression in plasma cell neoplasms.

Development and validation of a machine learning-based postoperative prognostic model for plasma cell neoplasia with spinal lesions as initial clinical manifestations: a single-center cohort study.

Spinal multiple myeloma (MM) and solitary plasmacytoma of bone (SPB), both plasma cell neoplasms, greatly affect patients' quality of life due to spinal involvement. Accurate prediction of surgical outcomes is crucial for personalized patient care, but systematic treatment guidelines and predictive models are lacking. This study aimed to develop and validate a machine learning (ML)-based model to predict postoperative outcomes and identify prognostic factors for patients with spinal MM and SPB. A retrospective analysis was conducted on patients diagnosed with MM or SPB from 2011 to 2015, followed by prospective data collection from 2016 to 2017. Patient demographics, tumor characteristics, clinical treatments, and laboratory results were analyzed as input features. Four types of ML algorithms were employed for model development. The performance was assessed using discrimination and calibration measures, and the Shapley Additive exPlanations (SHAP) method was applied for model interpretation. A total of 169 patients were included, with 119 for model training and 50 for validation. The Gaussian Naïve Bayes (GNB) model exhibited superior predictive accuracy and stability. Prospective validation on the 50 patients revealed an area under the curve (AUC) of 0.863, effectively distinguishing between 5-year survivors and non-survivors. Key prognostic factors identified included International Staging System (ISS) stage, Durie-Salmon (DS) stage, targeted therapy, and age. The GNB model has the best performance and high reliability in predicting postoperative outcomes. Variables such as ISS stage and DS stage were significant in influencing patient prognosis. This study enhances the ability to identify patients at risk of poor outcomes, thereby aiding clinical decision-making.

Non-invasive prenatal test identifies circulating cell-free DNA chromosomal abnormalities derived from clonal hematopoiesis in aggressive hematological malignancies

Liquid biopsy is a minimally invasive diagnostic tool for identification of tumor-related mutations in circulating cell-free DNA (cfDNA). The aim of this study was to investigate feasibility, sensitivity, and specificity of non-invasive prenatal test (NIPT) for identification of chromosomal abnormalities in cfDNA from a total of 77 consecutive patients with non-Hodgkin B-cell lymphomas, Hodgkin lymphoma (HL), or plasma cell dyscrasia. In this case series, half of patients had at least one alteration, more frequently in chromosome 6 (23.1%), chromosome 9 (20.5%), and chromosomes 3 and 18 (16.7%), with losses of chromosome 6 and gains of chromosome 7 negatively impacting on overall survival (OS), with a 5-year OS of 26.9% and a median OS of 14.6 months, respectively (P = 0.0009 and P = 0.0004). Moreover, B-cell lymphomas had the highest NIPT positivity, especially those with aggressive lymphomas, while patients with plasma cell dyscrasia with extramedullary disease had a higher NIPT positivity compared to conventional cytogenetics analysis and a worse outcome. Therefore, we proposed a NIPT-based liquid biopsy a complementary minimally invasive tool for chromosomal abnormality detection in hematological malignancies. However, prospective studies on larger cohorts are needed to validate clinical utility of NIPT-based liquid biopsy in routinely clinical practice.

Abstract CT001: Linvoseltamab, a B-cell maturation antigen-targeted T-cell-engaging bispecific antibody, induces deep and durable responses in patients with relapsed or refractory multiple myeloma including difficult-to-treat subgroups

Abstract Background We report pivotal results from the registrational filing data cut-off (DCO) of the 200 mg dose used in the LINKER-MM1 (NCT03761108) clinical trial, testing the safety and efficacy of linvoseltamab (a B-cell maturation antigen × CD3 antibody [Ab]) as treatment for relapsed/refractory multiple myeloma (RRMM). Methods Eligible patients had RRMM that either progressed on/after ≥3 lines of therapy that included a proteasome inhibitor (PI), an immunomodulatory drug (IMiD), and an anti-CD38 Ab or that was ≥double- (Phase 1) or triple- (Phase 2) class (PI/IMiD/anti-CD38 Ab) refractory. Phase 2 patients received intravenous linvoseltamab once a week through week 14, then once every 2 weeks (Q2W). Phase 2 patients achieving ≥very good partial response (VGPR) who have received treatment for ≥24 weeks transitioned to Q4W dosing. Primary endpoint was objective response rate (ORR) per Independent Review Committee (IRC). Secondary endpoints included duration of response (DOR), progression free survival (PFS), overall survival (OS), and safety. Results At DCO of Sep 8, 2023, median duration of follow-up for the 117 patients enrolled into the 200 mg dosing cohorts (phase 1+2) was 11.1 months (interquartile range 2.9-14.1). Median age was 70 years (26% ≥75), 17% were African American, 18% had International Staging System (ISS) stage III disease, 16% had extramedullary (excluding paramedullary) plasmacytomas (EMPs) ≥2 cm, 39% had high-risk cytogenetics, and 82% were ≥triple-class refractory. Linvoseltamab induced high rates of deep responses with an ORR of 71% including ≥complete response (CR) rate of 46%. Among all patients with ≥CR, 39% were documented minimal residual disease negative. These frequent and deep responses were observed across prespecified high-risk subgroups including patients with ISS stage III (ORR 62%; ≥CR 43%), and EMPs (ORR 53%; ≥CR 26%). Kaplan-Meier (KM) estimated median DOR was not reached (NR); estimated probability of ongoing response at 12 months was 78% (95% confidence interval [CI] 65-86). KM estimated PFS and OS were NR; and probability of PFS and OS at 12 months were 69% (95% CI 58-77) and 75% (65-82), respectively. The most common treatment emergent adverse event (TEAE) was cytokine release syndrome (CRS; any grade [Gr] 46%, Gr2 10%, Gr3 1%, Gr≥4 0%), which occurred mostly during step-up dosing of linvoseltamab with a median time to onset of 11 hours. Other common TEAEs were neutropenia (any Gr 41%, Gr 3-4 40%), anemia (39%, 31%), cough (36%, 0%), and diarrhea (35%, 2%). Infections occurred in 73% (Gr 3-4 34%) of patients. The frequency and severity of infections decreased after 6 months coincident with Q4W dosing. Conclusions Linvoseltamab induced high rates of deep and durable responses in patients with RRMM including those in high-risk subgroups. Linvoseltamab is associated with a generally predictable timing of CRS, and the Q4W response adapted schedule in patients with ≥VGPR may provide a substantial benefit for patient convenience and is associated with a reduced infection rate. Citation Format: Sundar Jagannath, Joshua Richter, Madhav V. Dhodapkar, James E. Hoffman, Hans C. Lee, Attaya Suvannasankha, Mansi R. Shah, Suzanne Lentzsch, Jeffrey A. Zonder, Rachid Baz, Joseph J. Maly, Swathi Namburi, Ka Lung Wu, Matthew Pianko, Rebecca Silbermann, Chang-Ki Min, Marie-Christiane Vekemans, Markus Munder, Ja Min Byun, Joaquín Martínez Lopez, Michelle DeVeaux, Dhruti Chokshi, Anita Boyapati, Anasuya Hazra, Karen Rodriguez Lorenc, Glenn S. Kroog, Yariv Houvras, Naresh Bumma. Linvoseltamab, a B-cell maturation antigen-targeted T-cell-engaging bispecific antibody, induces deep and durable responses in patients with relapsed or refractory multiple myeloma including difficult-to-treat subgroups [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 2 (Late-Breaking, Clinical Trial, and Invited Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(7_Suppl):Abstract nr CT001.

18F-FDG PET/CT in Solitary Extramedullary Plasmacytoma of the Penis.

A 72-year-old man presented with a painless penile mass for 3 months. Contrast-enhanced CT revealed heterogeneous enhancement, whereas 18F-FDG PET/CT displayed inhomogeneous 18F-FDG accumulation in the lesion without other abnormal activity. The histopathological examination from biopsied specimen confirmed the diagnosis of a plasmacytoma. However, the subsequent tests, including serum/urine immunofixation electrophoresis, serum/urine free light chain assay, and bone marrow smear/biopsy, did not show any abnormalities. The conclusive diagnosis was a solitary extramedullary plasmacytoma of the penis.

Nasal cavity extramedullary plasmacytoma: literature review and clinical experience

Abstract BACKGROUND. Extramedullary plasmacytoma is an extremely rare solitary plasma cell neoplasm that occurs in locations other than bone, without involving the bone marrow. It is commonly located in the upper aerodigestive tract. In the head and neck region, the most frequent location is the sinonasal region. MATERIAL AND METHODS. A systemic review in accordance with the PRISMA guidelines was done with research works in PubMed, Elsevier database, Cochrane library, Web of Science, Scopus, Crossref and Google Scholar. The search was carried out using the keywords “plasmacytoma and nose”, “extramedullary plasmacytoma”, “extramedullary plasmacytoma of nose”, “plasmacytoma and nasal cavity”, and “extramedullary plasmacytoma of nasal cavity”. RESULTS. We analysed 27 research works with a total number of 32 cases. The most common presenting symptoms were nasal cavity bleeding. The disease showed a male preponderance (78.1%). Bone erosion was seen in 7 cases. The histopathological examination showed plasma cells arranged predominantly as a uniform population or sheet-like appearance. A common immunohistochemical marker was CD138 (11 cases). Treatment was primarily radiotherapy (43.7%). We are also reporting a case of a 53-year-old male with plasmacytoma of the middle turbinate managed by wide resection and postoperative radiotherapy. CONCLUSION. Though a less common condition, in a case of polypoidal-like lesion with bleeding tendency, the clinician should keep in mind the possibility of extramedullary plasmacytoma. The diagnosis is made with histopathological examination and immunohisto-chemistry of the tissue involved. Treatment can be radiotherapy, surgery, or a combination of modalities.

Multiple Nasal Swellings and An Unusual Diagnosis: Extramedullary Plasmacytoma

Multiple Nasal Swellings and An Unusual Diagnosis: Extramedullary Plasmacytoma

Role of Immune Cells and Immunotherapy in Multiple Myeloma.

The clinical signs of multiple myeloma, a plasma cell (PC) dyscrasia, include bone loss, renal damage, and paraproteinemia. It can be defined as the uncontrolled growth of malignant PCs within the bone marrow. The distinctive bone marrow milieu that regulates the progression of myeloma disease involves interactions between plasma and stromal cells, and myeloid and lymphoid cells. These cells affect the immune system independently or because of a complicated web of interconnections, which promotes disease development and immune evasion. Due to the importance of these factors in the onset of disease, various therapeutic strategies have been created that either target or improve the immunological processes that influence disease progression. The immune system has a role in the mechanism of action of multiple myeloma treatments. The main contributions of immune cells to the bone marrow microenvironment, as well as how they interact and how immune regulation might lead to therapeutic effects, are covered in this study.

The role of therapeutic plasma exchange in plasma cell disorders.

Therapeutic plasma exchange (TPE) is an extracorporeal technique where patient's plasma containing pathogenic substances is separated and removed from the whole blood, while the cellular component is returned to the patient mixed with replacement solution via an apheresis machine. Due to its ability to remove pathogenic substances from plasma including immunoglobulins, TPE has proven efficacious in the management of various disorders across different medical disciplines, including plasma cell dyscrasias, which are characterized by the abundant secretion of non-functional immunoglobulins produced by an abnormally proliferating plasma cell clone. This review summarizes the current indications of TPE in plasma cell-related disorders and discusses its application, safety, and therapeutic effects.

Plasmacytoma and Amyloid Lymphadenopathy, FDG, and Fluorocholine.

A 56-year-old man with thoracal mass suspected of solitary plasmacytoma was referred for 18F-FDG PET-CT scan. His PET-CT revealed FDG-avid rib mass and cervical lesion at level 2. He also underwent 18F-fluorocholine (FCH) PET-CT to evaluate possible metastatic spread of the disease. FCH PET-CT showed increased uptake at the rib mass, while the cervical lesion was not FCH-avid. Biopsies confirmed rib lesion was a solitary plasmacytoma; however, the cervical lesion was an amyloid deposited lymph node. This case showed FCH PET-CT is a valuable companion of FDG scan for the evaluation of plasma cell dyscrasias with a better specificity.