Plasmacytoma as a Mimicker of Colonic Carcinoma in an Elderly Man

An Unprecedented Case of p190 BCR-ABL Chronic Myeloid Leukemia Diagnosed during Treatment for Multiple Myeloma: A Case Report and Review of the Literature

Case Reports in Hematology ◽

10.1155/2018/7863943 ◽

2018 ◽

Vol 2018 ◽

pp. 1-5

Author(s):

Kosuke Miki ◽

Naoshi Obara ◽

Kenichi Makishima ◽

Tatsuhiro Sakamoto ◽

Manabu Kusakabe ◽

...

Keyword(s):

Multiple Myeloma ◽

Bone Marrow ◽

Chronic Myeloid Leukemia ◽

Myeloid Leukemia ◽

Plasma Cells ◽

Bone Marrow Examination ◽

Bone Lesions ◽

Dexamethasone Treatment ◽

Lytic Bone Lesions

We report the case of a 76-year-old man who was diagnosed as having chronic myeloid leukemia (CML) with p190 BCR-ABL while receiving treatment for symptomatic multiple myeloma (MM). The diagnosis of MM was based on the presence of serum M-protein, abnormal plasma cells in the bone marrow, and lytic bone lesions. The patient achieved a partial response to lenalidomide and dexamethasone treatment. However, 2 years after the diagnosis of MM, the patient developed leukocytosis with granulocytosis, anemia, and thrombocytopenia. Bone marrow examination revealed Philadelphia chromosomes and chimeric p190 BCR-ABL mRNA. Fluorescence in situ hybridization also revealed BCR-ABL-positive neutrophils in the peripheral blood, which suggested the emergence of CML with p190 BCR-ABL. The codevelopment of MM and CML is very rare, and this is the first report describing p190 BCR-ABL-type CML coexisting with MM. Moreover, we have reviewed the literature regarding the coexistence of these diseases.

Download Full-text

Bone disease as the first manifestation of systemic AL-amyloidosis

Terapevticheskii arkhiv ◽

10.26442/00403660.2020.07.000775 ◽

2020 ◽

Vol 92 (7) ◽

pp. 85-89

Author(s):

L. P. Mendeleeva ◽

I. G. Rekhtina ◽

A. M. Kovrigina ◽

I. E. Kostina ◽

V. A. Khyshova ◽

...

Keyword(s):

Multiple Myeloma ◽

Bone Marrow ◽

Bone Disease ◽

Plasma Cells ◽

Interventricular Septum ◽

Bone Destruction ◽

Amyloid Deposition ◽

Bone Lesions ◽

Al Amyloidosis ◽

Linear Type

Our case demonstrates severe bone disease in primary AL-amyloidosis without concomitant multiple myeloma. A 30-year-old man had spontaneous vertebral fracture Th8. A computed tomography scan suggested multiple foci of lesions in all the bones. In bone marrow and resected rib werent detected any tumor cells. After 15 years from the beginning of the disease, nephrotic syndrome developed. Based on the kidney biopsy, AL-amyloidosis was confirmed. Amyloid was also detected in the bowel and bone marrow. On the indirect signs (thickening of the interventricular septum 16 mm and increased NT-proBNP 2200 pg/ml), a cardial involvement was confirmed. In the bone marrow (from three sites) was found 2.85% clonal plasma cells with immunophenotype СD138+, СD38dim, СD19-, СD117+, СD81-, СD27-, СD56-. FISH method revealed polysomy 5,9,15 in 3% of the nuclei. Serum free light chain Kappa 575 mg/l (/44.9) was detected. Multiple foci of destruction with increased metabolic activity (SUVmax 3.6) were visualized on PET-CT, and an surgical intervention biopsy was performed from two foci. The number of plasma cells from the destruction foci was 2.5%, and massive amyloid deposition was detected. On CT scan foci of lesions differed from bone lesions at multiple myeloma. Bone fragments of point and linear type (button sequestration) were visualized in most of the destruction foci. The content of the lesion was low density. There was no extraossal spread from large zones of destruction. There was also spontaneous scarring of the some lesions (without therapy). Thus, the diagnosis of multiple myeloma was excluded on the basis based on x-ray signs, of the duration of osteodestructive syndrome (15 years), the absence of plasma infiltration in the bone marrow, including from foci of bone destruction by open biopsy. This observation proves the possibility of damage to the skeleton due to amyloid deposition and justifies the need to include AL-amyloidosis in the spectrum of differential diagnosis of diseases that occur with osteodestructive syndrome.

Download Full-text

The Evolution in The Treatment of Multiple Myeloma Towards Targeted Magnetic Molecularly Imprinted Nanomedicines

Edelweiss: Cancer Open Access ◽

10.33805/2689-6737.101 ◽

2015 ◽

pp. 1-2

Author(s):

Edgar Pérez-Herrero

Keyword(s):

Multiple Myeloma ◽

Bone Marrow ◽

Bacterial Infections ◽

Plasma Cells ◽

The Body ◽

Western World ◽

Bone Lesions ◽

Non Hodgkin Lymphoma ◽

Clonal Proliferation ◽

Tract Infections

Multiple myeloma is the second more frequently haematological cancer in the western world, after non-Hodgkin lymphoma, being about the 1-2 % of all the cancers cases and the 10-13% of hematologic diseases. The disease is caused by an uncontrolled clonal proliferation of plasma cells in the bone marrow that accumulate in different parts of the body, usually in the bone marrow, around some bones, and rarely in other tissues, forming tumor deposits, called plasmocytomas. This uncontrolled clonal proliferation of plasma cells produces the secretion of an abnormal monoclonal immunoglobulin (paraprotein or M-protein) and prevents the formation of the other antibodies produced by the normal plasma cells that are destroyed. The anormal secretion of paraproteins unbalance the osteoblastosis and osteoclastosis processes, leading to bone lesions that cause lytic bone deposits and the release of calcium from bones (hypercalcemia) that may produce renal failure. Regions affected by bone lesions are the skull, spine, ribs, sternum, pelvis and bones that form part of the shoulders and hips. The substitution of the healthy bone marrow by infiltrating malignant cells and the inhibition of the normal production of red blood cells produce anaemia, thrombocytopenia and leukopenia. Multiple myeloma patients are immunosuppressed because of leukopenia and the abnormal immunoglobulin production caused by the uncontrolled clonal proliferation of plasma cells, being susceptible to bacterial infections, like pneumonias and urinary tract infections. The interaction of immunoglobulin with hemostatic mechanisms may lead to haemorrhagic diathesis or thrombosis. Also, disorders of the central and peripheral nervous system are part of the disease, being the more common neurological manifestations the spinal cord compressions and the peripheral neuropathies.

Download Full-text

Extensive Bone Marrow Infiltration and Abnormal Free Light Chain Ratio Identifies Patients with Smoldering Myeloma At High Risk for Progression to Symptomatic Disease,

Blood ◽

10.1182/blood.v118.21.3926.3926 ◽

2011 ◽

Vol 118 (21) ◽

pp. 3926-3926

Author(s):

Efstathios Kastritis ◽

Lia A Moulopoulos ◽

Maria Gkotzamanidou ◽

Dimitra Gika ◽

Maria Roussou ◽

...

Keyword(s):

Bone Marrow ◽

High Risk ◽

Light Chain ◽

Plasma Cells ◽

Bone Lesions ◽

Symptomatic Disease ◽

Lytic Bone Lesions ◽

Risk Of Progression ◽

Bone Marrow Plasma ◽

Substantial Risk

Abstract Abstract 3926 Asymptomatic/smoldering multiple myeloma (SMM) is a proliferative plasma cell disorder characterized by a substantial risk of progression to symptomatic myeloma. According to current recommendations, patients with SMM should be followed without treatment until they develop symptomatic disease. However, the risk of progression to symptomatic myeloma varies between different series and for individual patients; thus, significant effort is needed in order to identify factors that could discriminate those who are at high risk for progression. Such patients should be followed closer and should be considered candidates for clinical trials. In order to evaluate previously recognized risk factors and study patterns of progression we analyzed our series of patients with SMM, who have been diagnosed and followed in the Department of Clinical Therapeutics in Athens, Greece. SMM was defined as serum monoclonal (M) protein (IgG or IgA) level of ≥3 g/dL and/or bone marrow plasma cells ≥10%, absence of end-organ damage, such as lytic bone lesions, anemia, hypercalcemia, or renal failure, that can attributed to a plasma cell proliferative disorder (IMWG criteria, Br J Haematol 2003;121:749–57). Progression to symptomatic myeloma was defined as per the IMWG proposed criteria. We analyzed 95 patients with SMM, 53% of whom were females, 70% had IgG heavy chain, 22% had IgA, 5% had a biclonal SMM and 3% had light chain only SMM, while 65% had a kappa light chain and 35% a lambda light chain. Median infiltration by clonal plasma cells in BM trephine biopsy was 20% (range 10–90%), 10% of patients had ≥60% clonal plasma cells in BM biopsy. Fifty patients had MRI of the spine at the time of diagnosis of SMM and 19.5% had an abnormal pattern of BM infiltration (diffuse, focal or variegated pattern). In patients with available bone marrow immunohistochemistry data, 61% had clonal plasma positive for CD56, 17% for CD20 and 19% for cyclin D1. The median follow up of the cohort was 27 months (range 1–253 months) and 23 (24%) patients have progressed to symptomatic myeloma. The one-year, 2-year and 3-year cumulative probability of progression was 7%, 12% and 20% respectively. Nine patients (9.5%) progressed within the first two years from the diagnosis of SMM. All these patients had an M-protein of ≥1 g/dl (10 g/L), 67% had bone marrow plasma cells >60% and 80% had an abnormal MRI pattern of BM infiltration. The 3-year probability of progression to symptomatic myeloma was 4%, 18% and 87% for patients with <20%, 20–59% and ≥60% clonal plasma cells in bone marrow biopsy (P<0.001). The 2-year probability of progression to symptomatic myeloma was 0%, 13% and 60% for patients with <20%, 20–59% and ≥60% clonal plasma cells in BM biopsy (P<0.001). Patients with significantly abnormal free light chain ratio (either kappa/lambda ≥8 or kappa/lambda ≤0.125, according to Dispenzieri et al, Blood 2008;111:785–9) had a 3-year probability of progression to symptomatic MM of 41% vs. 15% (p=0.07). There was no significant difference in the risk of progression to symptomatic MM for patients with IgA vs. IgG myeloma. In multivariate analysis, abnormal FLC ratio less than 0.125 or more than 8 (HR: 6.4, 95% CI 1.3–34.5 p=0.032) and BM clonal plasma cells infiltration ≥60% (HR: 23, 95% CI 5–125, p<0.001) were independent risk factors for progression to symptomatic myeloma. Progression to symptomatic MM was manifested by the development of anemia in 52% of patients who progressed to symptomatic MM, development of lytic bone lesions or pathologic fracture in 48%, an increase of serum creatinine to ≥2 mg/dl in 13%, development of a soft tissue plasmacytoma in 4% and development of hypercalcemia in 4%. In conclusion, in our series of patients the 3-year probability of progression to symptomatic myeloma is about 20%, but there is a subgroup of patients with extensive bone marrow infiltration (≥60%) and highly abnormal FLC ratio, who have a substantial risk of progression to symptomatic disease within the first two years from the diagnosis of SMM. These high risk patients may also have other features such as abnormal MRI of the spine. Patients at high risk for progression should be considered for clinical trials evaluating the role of treatment before the development of symptomatic disease, which in most cases is manifested with anemia and/or lytic bone disease or pathologic fractures. Disclosures: No relevant conflicts of interest to declare.

Download Full-text

Multiple Myeloma Associated GI Polyposis

Blood ◽

10.1182/blood.v120.21.5009.5009 ◽

2012 ◽

Vol 120 (21) ◽

pp. 5009-5009

Author(s):

Nassim Nabbout ◽

Mohamad El Hawari ◽

Thomas K. Schulz

Keyword(s):

Multiple Myeloma ◽

Bone Marrow ◽

Plasma Cells ◽

Conflicts Of Interest ◽

Case Reports ◽

Bone Marrow Failure ◽

Bone Lesions ◽

Rare Manifestation ◽

History Of ◽

Central Ulceration

Abstract Abstract 5009 Multiple myeloma is a neoplastic proliferation of monoclonal plasma cells that can result in osteolytic bone lesions, hypercalcemia, renal impairment, bone marrow failure, and the production of monoclonal gammopathy. The gastrointestinal tract is rarely involved in myeloma. GI polyposis is a rare manifestation of extra-medullary disease in multiple myeloma. Such cases usually present as gastrointestinal hemorrhage or intestinal obstruction. A 53-year-old African American male recently diagnosed with multiple myeloma presented with three-day history of rectal bleed and fatigue. EGD showed multiple raised, polypoid, rounded lesions with a superficial central ulceration in the stomach. Colonoscopy showed similar lesions in the ascending and transverse areas of the colon that ranged in size from 5 to 16 mm in diameter. Biopsies showed that these polyps were made of plasma cells. A bone marrow biopsy showed diffuse involvement (greater than 90%) of bone marrow with multiple myeloma with anaplastic features. The patient was started on bortezomib at diagnosis, however, he passed away a few weeks later. This type of metastatic disease has been described in isolated case reports in the literature, while solitary GI plasmacytoma has been reported more frequently. In rare cases, multiple myeloma can involve the GI tract which may lead to bleed or obstruction. This involvement is likely a marker of aggressivity. This example of extra-medullary disease in myeloma is an uncommon variant with features of poor prognosis and dedifferentiation. Disclosures: No relevant conflicts of interest to declare.

Download Full-text

Predictive Significance of Serum Beta 2-Microglobulin Levels and M-Protein Velocity for Symptomatic Progression of Smoldering Multiple Myeloma

Blood ◽

10.1182/blood.v124.21.3379.3379 ◽

2014 ◽

Vol 124 (21) ◽

pp. 3379-3379 ◽

Cited By ~ 7

Author(s):

Tsuyoshi Muta ◽

Shinsuke Iida ◽

Kosei Matsue ◽

Kazutaka Sunami ◽

Jun Isoda ◽

...

Keyword(s):

Multiple Myeloma ◽

Cumulative Incidence ◽

Plasma Cells ◽

M Protein ◽

Bone Lesions ◽

Landmark Point ◽

Protein Levels ◽

Lytic Bone Lesions ◽

Bone Marrow Plasma ◽

Beta 2 Microglobulin

Abstract Background: Smoldering multiple myeloma (SMM) has been defined as precursor state to symptomatic multiple myeloma (MM). Mayo Clinic demonstrated that the presence of bone marrow plasma cells (BMPC) ≥ 10% and M protein levels ≥ 3 g/dL significantly associated with early progression to symptomatic MM and the serum free-light chain (FLC) ratio of < 0.125 or 8 < was an important additional predictors of progression. PETHEMA showed that the proportion of aberrant plasma cells (aPCs) within the BMPC > 95% as assessed by flow cytometry was another important variable for progression. However, NIH demonstrated the discordance of these two risk models. The aim of this project is to develop the method to predict the symptomatic progression more definitely by simple parameters, usually available at medical practice. Methods: We employed the nation-wide retrospective study. The clinical data of SMM patients were collected from 61 medical centers in Japan and risk predictors of progression to symptomatic MM were analyzed. The diagnosis of SMM is made by the presence of the ratio of bone marrow plasma cells (BMPCs) ≥ 10% or serum M-protein levels ≥ 3 g/dL, and the absence of any myeloma derived end-organ damage. Eligible patients were aged 18 to 90 years, previously untreated, and diagnosed between 2000 and 2012. This study was approved by the institutional review board at all participating institutions. Results: Total 301 patients fulfilled the inclusion criteria. The median age was 67 years (rang 27 to 90). IgG is the major (80%) compared to IgA (15%) or Bence Jones protein (3%). Total 145 patients developed to symptomatic MM. The symptoms consisted of anemia in 66%, lytic bone lesions in 43%, and renal impairment in 10%. Both anemia and lytic bone lesions were seen in 16%. The median time to progression was 4.3 years. The cumulative incidence of progression was 30.7% at 2 years, 50.0% at 4 years, 59.8% at 6 years, and 68.6% at 8 years. Based on multivariate analysis, we firstly identify the serum beta 2-microglobulin (B2MG) levels ≥ 2.5 mg/L as a predictor for the early progression (HR 1.59; 95% CI, 1.11 to 2.29, p = 0.01), as well as the known factors: presence of both BMPC ≥ 10% and M protein levels ≥ 3 g/dL (HR 1.89; 95% CI, 1.31 to 2.73, p = 0.0007), IgA or Bence Jones type (HR:1.61; 95%CI, 1.04 to 2.49, p = 0.03), and immunoparesis (HR:1.88; 95%CI, 1.14 to 3.08, p = 0.01). FLC ratio was examined in 52 patients. A significant association with high risk of progression was observed in patients with FLC ratio of < 0.0625 or 16 < (P = 0.04), but not in those with the ratio of < 0.125 or 8 < (P = 0.09). Cytogenetic abnormality was examined with FISH in 82 patients. The cumulative incidence of progression in patients with either t(4;14), t(14;16), or del(17p) was not significantly different from those without such chromosomal aberration (P = 0.4). Notably, we firstly focused on the rate of rise of the M-protein levels over time which is referred to as the "M-protein velocity". We employed the linear regression analysis to estimate the gradient to assess the M-protein velocity of each patient. The receiver operating characteristics curve analysis showed that the M-protein velocity of 1.035 mg/dL/day was a risk-stratification cut-off point with a high specificity of 0.96 and with a moderate sensitivity of 0.60. Based on the landmark analysis, the serum B2MG levels ≥ 2.5 mg/L at diagnosis (HR 2.76; 95% CI, 1.69 to 4.51, P = 5 x 10–5) and the M-protein velocity > 1 mg/dL/day before the 18-month landmark point (HR 2.27; 95% CI, 1.30 to 3.95, P = 4 x 10–3) had independently correlated with subsequent progression to symptomatic MM. The cumulative incidence of progression of the patients with both the serum B2MG levels ≥ 2.5 mg/L at diagnosis and the M-protein velocity > 1 mg/dL/day showed 67.5% at 2 years, 75.6% at 3 years and 100% at 6.3 years after the landmark point. Conclusions: We identify the novel risk factors consisted of serum B2MG levels ≥ 2.5 mg/L and the M-protein velocity > 1 mg/dL/day for subsequent symptomatic progression. Theoretically, it is possible to emphasis that the serum B2MG levels represent the initial tumor burden of SMM and the M-protein velocity reflects the the growth rate of tumor cells. These results also suggest that the quantification of time-dependent change of measured values should be taken into consideration for the precise prediction of symptomatic progression. This study is supported by the National Cancer Center Research and Development Fund in Japan. Disclosures No relevant conflicts of interest to declare.

Download Full-text

MR Imaging of Multiple Myeloma in Tumour Mass Measurement at Diagnosis and during Treatment

Acta Radiologica ◽

10.1177/028418519503600102 ◽

1995 ◽

Vol 36 (1) ◽

pp. 9-14 ◽

Cited By ~ 17

Author(s):

K. Carlson ◽

G. Åström ◽

R. Nyman ◽

H. Ahlström ◽

B. Simonsson

Keyword(s):

Multiple Myeloma ◽

Bone Marrow ◽

Mr Imaging ◽

Mass Measurement ◽

Bone Lesions ◽

Tumour Mass ◽

Efficacy Evaluation ◽

Clinical Criteria ◽

Lytic Bone Lesions

The bone marrow of the spine, pelvis and proximal femora was examined with MR imaging at diagnosis in 30 cases of multiple myeloma (MM), and during treatment on 69 occasions. The MR pattern was normal, focal or diffuse and correlated to stage. A tumour mass index (TMI) was calculated by estimating the total myeloma mass visualised at MR imaging. The TMI correlated significantly with stage, lytic bone lesions, serum calcium, serum β-2-microglobulin and survival. No abnormalities were seen at MR investigation in 4 of 6 patients classified as stage II because of osteoporosis only. Therapy efficacy evaluation with MR imaging corresponded to clinical evaluation on 54 of the 69 occasions. MR examination of bone marrow in MM patients can be used for tumour mass assessment, both at diagnosis and during follow-up. Valuable information can be obtained when the tumour mass is difficult to estimate using clinical criteria, e.g. in non-secretory MM or when osteoporosis is the only variable indicating an increase in the tumour mass.

Download Full-text

Myeloma progenitors in the blood of patients with aggressive or minimal disease: engraftment and self-renewal of primary human myeloma in the bone marrow of NOD SCID mice

Blood ◽

10.1182/blood.v95.3.1056.003k26_1056_1065 ◽

2000 ◽

Vol 95 (3) ◽

pp. 1056-1065 ◽

Cited By ~ 91

Author(s):

Linda M. Pilarski ◽

Gail Hipperson ◽

Karen Seeberger ◽

Eva Pruski ◽

Robert W. Coupland ◽

...

Keyword(s):

Bone Marrow ◽

High Frequency ◽

Plasma Cells ◽

Scid Mice ◽

Bone Lesions ◽

Recipient Mouse ◽

Self Renewal ◽

Myeloma Cells ◽

Lytic Bone Lesions ◽

Minimal Disease

The myelomagenic capacity of clonotypic myeloma cells in G-CSF mobilized blood was tested by xenotransplant. Intracardiac (IC) injection of NOD SCID mice with peripheral cells from 5 patients who had aggressive myeloma led to lytic bone lesions, human Ig in the serum, human plasma cells, and a high frequency of clonotypic cells in the murine bone marrow (BM). Human B and plasma cells were detected in BM, spleen, and blood. Injection of ex vivo multiple myeloma cells directly into the murine sternal BM (intraosseus injection [IO]) leads to lytic bone lesions, BM plasma cells, and a high frequency of clonotypic cells in the femoral BM. This shows that myeloma has spread from the primary injection site to distant BM locations. By using a cellular limiting dilution PCR assay to quantify clonotypic B lineage cells, we confirmed that peripheral myeloma cells homed to the murine BM after IC and IO injection. The myeloma progenitor undergoes self-renewal in murine BM, as demonstrated by the transfer of human myeloma to a secondary recipient mouse. For 6 of 7 patients, G-CSF mobilized cells from patients who have minimal disease, taken at the time of mobilization or after cryopreservation, included myeloma progenitors as identified by engraftment of clonotypic cells and/or lytic bone disease in mice. This indicates that myeloma progenitors are mobilized into the blood by cyclophosphamide/G-CSF. Their ability to generate myeloma in a xenotransplant model implies that such progenitors are also myelomagenic when reinfused into patients, and suggests the need for an effective strategy to purge them before transplant.

Download Full-text

Macrofocal Multiple Myeloma in Young Patients: A Distinct Entity with Favorable Prognosis.

Blood ◽

10.1182/blood.v106.11.3399.3399 ◽

2005 ◽

Vol 106 (11) ◽

pp. 3399-3399

Author(s):

Meletios A. Dimopoulos ◽

Anastasia Pouli ◽

Athanasios Angnostopoulos ◽

Panagiotis Repoussis ◽

Argyris Symeonidis ◽

...

Keyword(s):

Multiple Myeloma ◽

Bone Marrow ◽

Renal Impairment ◽

Median Survival ◽

Young Patients ◽

Primary Treatment ◽

Bone Lesions ◽

High Dose ◽

Distinct Entity ◽

Lytic Bone Lesions

Abstract Introduction: Most patients with multiple myeloma (MM) present with multiple lytic bone lesions, extensive marrow plasmacytosis and anemia. Furthermore in several of them hypercalcemia and renal impairment are evident at diagnosis. Over the years, we have seen occasional young patients with MM who presented with multiple lytic bone lesions but without intervening infiltration of bone marrow i.e. a pattern consisting of macrofocal MM. Patients and methods: In order to assess the clinical and laboratory features and the outcome of patients with macrofocal MM we performed a retrospective analysis of symptomatic patients with MM ≤40 years of age at diagnosis who received primary treatment over a 20 year period (from January 1, 1985 to December 31, 2004). The diagnosis of macrofocal MM required the presence of lytic bone lesions and the absence of obvious bone marrow plasmacytosis (BMPC<10%) on bone marrow aspirate and/or biopsy. Results: Among 51 patients ≤40 years at the time of initial treatment, 10 patients fulfilled the criteria of macrofocal MM. Patients’ median age, gender, myeloma heavy and light chain were similar among patients of the 2 groups. When compared with patients with typical MM, patients with macrofocal pattern were less anemic (p=0.018), none had hypercalcemia (p=0.1), renal impairment (p=0.17), elevated serum LDH (p=0.14), or stage 3 according to the International Staging System (ISS) (p=0.13). Four of the 10 patients with macrofocal MM versus 0 of 41 patients with typical MM (p=<0.01) had a prior diagnosis of solitary bone plasmacytoma. Approximately 80% of patients in both groups received primary treatment based on high-dose dexamethasone regimens (VAD or VAD-like regimens). An objective response was noted in 55% of patients with macrofocal MM and in 50% of patients without this pattern. The median survival of patients with typical MM was 57 months and has not been reached in patients with macrofocal MM (p=0.087). In the latter group of patients, median survival is projected to exceed 8 years. The 10 year survival rate is 20% and 5% in patients with or without macrofocal myeloma respecrively. Conclusion: Our analysis indicates that macrofocal MM is a distinct entity in young patients with MM. Despite multiple lytic bone lesions, such patients have features of low tumor burden and an improved survival when compared with young patients with typical MM. Future studies including gene profiling may reveal potential biological differences among the two groups of patients.

Download Full-text

Generation of a Novel, Multi-Stage, Progressive, and Transplantable Model of Multiple Myeloma

Blood ◽

10.1182/blood.v120.21.327.327 ◽

2012 ◽

Vol 120 (21) ◽

pp. 327-327

Author(s):

Takashi Asai ◽

Silvia Menendez ◽

Delphine Ndiaye-Lobry ◽

Anthony R Deblasio ◽

Kazunori Murata ◽

...

Keyword(s):

Multiple Myeloma ◽

Bone Marrow ◽

Animal Model ◽

B Cells ◽

Plasma Cell ◽

Plasma Cells ◽

Class Switch Recombination ◽

Class Switch ◽

Multi Stage ◽

Plasma Cell Neoplasms

Abstract Abstract 327 Multiple myeloma is characterized by the progressive expansion of monoclonal plasma cells in the bone marrow, which leads to the production of serum and/or urine monoclonal proteins and systemic complications including lytic bone lesions, renal abnormalities hypercalcemia, and infections. Although the treatment of multiple myeloma has vastly improved, multiple myeloma remains a generally incurable disease. Transgenic mouse models have been generated that develop plasma cell accumulations or myeloma, however these models are quite imperfect in mimicking the human disease. Quite serendipitously, we have generated a multi-stage, progressive, and transplantable mouse model of multiple myeloma, crossing a genetically modified mouse with aberrant class switch recombination with another modified mouse that has elevated DNA damage response signaling. We have reported that cells expressing the hypermorphic Rad50s allele show constitutive ATM activation, leading to cancer predisposition and aggressive hematopoietic failure in Rad50s/s mice. While deficiency of the transcription factor Mef/Elf4, which regulates the quiescence of hematopoietic stem/progenitor cells, can mitigate hematopoietic failure observed in Rad50s/s mice, we found that 70% of Mef−/−Rad50s/s mice more than 200 days old died from multiple myeloma, plasmacytoma, or plasma cell leukemia, confirmed by pathology, immunohistochemistry, flowcytometry (CD138/B220 profiles), and PCR analysis for VDJ recombination. Prior to the onset of the plasma cell neoplasms, the Mef−/−Rad50s/s mice show abnormal plasma cell accumulation in the peripheral blood and bone marrow, which worsens with age. As the mice age, they also develop progressive increases in g-globulin levels and decreases in serum albumin levels. Monoclonal protein peaks were frequently observed in the serum of mice older than 200 days, and in step with the progressive nature of these manifestations, anemia and lower bone mineral density becomes apparent as the mice further age. Overall, the median survival of the Mef−/−Rad50s/s mice is approximately 470 days. The plasma cell neoplasms derived from Mef−/−Rad50s/s mice can be transplanted into recipient mice and the onset of the transplanted disease is markedly accelerated, to approximately 4 weeks post transplantation. Thus, the transplanted neoplastic Mef−/−Rad50s/s plasma cells appear to be more aggressive than the original ones. Taken together, our findings suggest that the Mef−/−Rad50s/s animal model can recapitulate the spectrum and pace of human plasma cell neoplasms, including the progression from monoclonal gammopathy to multiple myeloma. Class switch recombination is facilitated in Mef−/−Rad50s/s B cells in vitro, compared with control, Mef−/−, and Rad50s/s B cells, thus the plasma cell neoplasms found in Mef−/−Rad50s/s mice may result from Rad50s-driven oncogenesis. This novel Mef−/−Rad50s/s myeloma animal model should be useful for the drug screening of novel anti-myeloma compounds, as well as defining the pathogenesis of multiple myeloma/plasma cell neoplasms. Disclosures: No relevant conflicts of interest to declare.

Download Full-text