Hematogenous extramedullary relapse in multiple myeloma - a multicenter retrospective study in 127 patients.

The current study assesses the characteristics and outcomes of multiple myeloma (MM) patients, treated with novel agents for hematogenous extramedullary (HEMM) relapse. Consecutive patients diagnosed with HEMM between 2010-2018 were included. Patients' characteristics at diagnosis and at HEMM presentation, response to treatment, survival and factors predicting survival were recorded and analyzed. A group of 127 patients, all diagnosed with HEMM by imaging (87.3%) and/or biopsy (79%), were included. Of those, 44% were initially diagnosed with ISS3, 57% presented with plasmacytomas, and 30% had high-risk cytogenetics. Median time to HEMM was 32 months. In multivariate analysis, ISS3 and bone plasmacytoma predicted shorter time to HEMM (P = .005 and P = .008, respectively). Upfront autograft was associated with longer time to HEMM (P = .002). At HEMM, 32% of patients had no BM plasmacytosis, 20% had non-secretory disease and 43% had light-chain disease. Multiple HEMM sites were reported in 52% of patients, mostly involving soft tissue, skin (29%), and pleura/lung (25%). First treatment for HEMM included proteasome inhibitors (50%), immunomodulatory drugs (IMiDs) (39%), monoclonal antibodies (10%), and chemotherapy (53%). Overall response rate (ORR) was 57%. IMiDs were associated with higher ORR (HR 2.2, 95% CI 1.02-4.7, P = .04). Median survival from HEMM was 6 months (CI 95% 4.8-7.2). Failure to achieve ≥VGPR was the only significant factor for worse OS in multivariate analyses (HR = 9.87, CI 95% 2.35 - 39, P = .001). In conclusion, HEMM occurs within 3 years of initial myeloma diagnosis and is associated with dismal outcome. The IMiDs might provide a higher response rate, and achievement of ≥VGPR predicts longer survival.

Circulating Tumour DNA Analysis for Tumour Genome Characterisation and Monitoring Disease Burden in Extramedullary Multiple Myeloma.

Mutational characterisation in extramedullary multiple myeloma (EM-MM) patients is challenging due to inaccessible EM plasmacytomas, unsafe nature of multiple biopsies and the spatial and temporal genomic heterogeneity apparent in MM (Graphical abstract). Conventional monitoring of disease burden is through serum markers and PET-CT, however these modalities are sometimes inadequate (serum markers), not performed in a timely manner (PET-CT) and uninformative for identifying mutations driving disease progression. DNA released into the blood by tumour cells (ctDNA) contains the predominant clones derived from the multiple disease foci. Blood-derived ctDNA can, therefore, provide a holistic illustration of the major drivers of disease progression. In this report, the utility of ctDNA, as an adjunct to currently available modalities in EM-MM, is presented for a patient with EM and oligosecretory (OS) disease. Whole exome sequencing of contemporaneously acquired tumour tissue and matched ctDNA samples revealed the presence of spatial and temporal genetic heterogeneity and the identification of pathways associated with drug resistance. Longitudinal monitoring of plasma samples revealed that ctDNA can be utilised to define the dynamic clonal evolution co-existent with disease progression and as an adjunct non-invasive marker of tumour burden.

How We Manage Patients with Plasmacytomas.

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

Serum-free light-chain analysis in diagnosis and management of multiple myeloma and related conditions.

The introduction of the serum-free light-chain (S-FLC) assay has been a breakthrough in the diagnosis and management of plasma cell dyscrasias, particularly monoclonal light-chain diseases. The first method, proposed in 2001, quantifies serum-free light-chains using polyclonal antibodies. More recently, assays based on monoclonal antibodies have entered into clinical practice. S-FLC measurement plays a central role in the screening for multiple myeloma and related conditions, in association with electrophoretic techniques. Analysis of S-FLC is essential in assessing the risk of progression of precursor diseases to overt plasma cell dyscrasias. It is also useful for risk stratification in solitary plasmacytoma and AL amyloidosis. The S-FLC measurement is part of the new diagnostic criteria for multiple myeloma, and provides a marker to follow changes in clonal substructure over time. Finally, the evaluation of S-FLC is fundamental for assessing the response to treatment in monoclonal light chain diseases.

A retrospective study of correlation of morphologic patterns, MIB1 proliferation index, and survival analysis in 134 cases of plasmacytoma.

Plasmacytoma classified into solitary plasmacytoma of bone (SPB) and extramedullary plasmacytoma (EMP) is characterized by infiltrate of plasma cells of diverse maturity and by their monoclonal immunoglobulin products. Both SPB and EMP represent different groups of neoplasm in terms of location, tumor progression, and overall survival rate. There is a need for features that indicate likelihood of myeloma in patients with plasmacytoma without other manifestations. This study was an attempt to study the morphologic patterns of plasmacytoma (SPB and EMP), MIB1 proliferation index, and correlation of these with clinicopathologic features and survival of the patients. The study group comprised of 134 cases of plasmacytoma (88 SPB and 46 EMP) over duration of 8 years and were graded as per Bartl's histologic grading system. Commonest site was vertebral body in SPB (36%) and upper aerodigestive tract in EMP (48%). On serum electrophoresis, overall M band was detected in 41% cases. Both SPB and EMP on histology revealed similar morphologic features. MIB1 proliferation index ranged from less than 1% to 80%. It was slightly higher in EMP in comparison with SPB (P value = .002). Seventy percent of cases, which progressed to multiple myeloma (MM) showed MIB1 labeling index more than 10%; however, it was not statistically significant in predicting the disease progression. With the median follow-up of 19 months (range, 1-99 months), 10 SPB had disease progression of which 7 converted to MM, and 3 developed EMP, with a median interval of 21 months (range, 8-75 months) for the development of MM and 3 months (range, 3-9 months) for the progression to EMP. Five-year survival for EMP varied by site, with poorest survival in brain/central nervous system EMP as compared with EMP at other sites. To conclude, grade and MIB1 proliferation index help in predicting aggressive course in plasmacytoma.

Solitary extramedullary plasmocytoma of the thyroid: a case report and histological approach to plasma cells infiltrate in the thyroid gland.

BACKGROUND: Solitary extramedullary plasmacytoma (SEP) is a rare malignant neoplasm arising from plasma cells. SEP mostly occurs in the upper respiratory tract. Thyroid gland is rarely affected (<78 cases). METHODS/RESULTS: We describe the case of a 78-year-old woman presenting a rapidly enlarging palpable thyroid mass. Neck computed tomography scan showed enlargement of both thyroid lobes. Laboratory tests were normal, including serum protein level with no monoclonal gamma globulin peak. Cytology was suspicious for lymphoma. Biopsy showed an infiltrating neoplasm composed of atypical tumor cells with abundant cytoplasm and eccentric nuclei. These revealed diffuse immunoreactivity for CD138 and predominant staining for immunoglobulin kappa light chains. Clinical workup for multiple myeloma was negative. CONCLUSIONS: SEP should be considered in the differential diagnosis of a rapidly enlarging thyroid nodule and be distinguished from involvement of thyroid in multiple myeloma, mucosa-associated lymphoid tissue lymphoma, plasma cell granuloma and medullary carcinoma. Clinical correlation and immunohistochemistry are crucial in avoiding pitfalls.

Lambda light chain myeloma presenting as nodular hepatic lesion: a clinical rarity.

We report a case of a 63-year-old lady presenting with pain in the right hypochondrium, jaundice, anorexia, and firm tender hepatomegaly with remarkably high serum alkaline phosphatase. Abdominal ultrasonography revealed a hypoechoic solid space-occupying lesion in right lobe of liver which was cytologically diagnosed as hepatic plasmacytoma. Serum and urine immunofixation electrophoresis, serum free light chain ratio, and bone marrow examination further confirmed the presence of lambda light chain multiple myeloma in the background. The patient achieved complete remission after four cycles of induction therapy with thalidomide and dexamethasone protocol and consolidated with further four cycles of the same regimen.

Serum free light chain analysis in the diagnosis and management of multiple myeloma and related conditions.

The serum free light chain (FLC) assay is an important tool in the management of patients with monoclonal gammopathies. MEDLINE, the Cochrane Central Register of Controlled Trials and the Cochrane Database of Systematic Reviews from January 2000 through July 2013, were used as data sources. The available evidence is rather weak. For screening of multiple myeloma and related conditions, the association of the FLC assay with the traditional serum tests avoids urine study. Screening for immunoglobulin light-chain (AL) amyloidosis or other rare syndromes requires the urine examination. FLC measurement is used in the assessment of the risk of progression of precursor diseases to overt myeloma, and for risk stratification in solitary plasmacytoma, multiple myeloma and AL amyloidosis. In patients with oligosecretory myeloma and AL amyloidosis, the quantification of FLC is essential for monitoring and categorization of response to therapy. Further studies with improved design are warranted to strengthen the available evidence.

Serum protein electrophoresis in the evaluation of lytic bone lesions.

Serum protein electrophoresis (SPEP) is often obtained at the initial evaluation of a radiolucent bone lesion of unknown etiology. The results are considered convincing evidence of the presence or absence of a plasma cell neoplasm. The sensitivity and specificity of the SPEP have not been reported in this clinical scenario. Our purpose is to assess the diagnostic value of the SPEP in the initial work-up of the radiolucent bone lesion. We identified 182 patients undergoing evaluation of a radiolucent bone lesion that included tissue biopsy and an SPEP value. We then calculated the sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of SPEP as a diagnostic test for a plasma cell neoplasm in this clinical scenario. Forty-six of 182 (25.3%) patients in our series were diagnosed with a plasma cell neoplasm by histopathologic analysis. The sensitivity of SPEP was 71% and the specificity was 83%. PPV was 47% and NPV was 94%. When analyzing only those presenting with multiple lesions, the percentage of patients diagnosed with multiple myeloma increased to 44.7% (34 of 76 patients). The SPEP, however, did not have a substantially increased diagnostic accuracy with sensitivity of 71%, specificity 79%, PPV 40% and NPV 93%. SPEP lacks sensitivity and positive predictive value to provide a definitive diagnosis of myeloma in radiolucent bone lesions, but has a high negative predictive value which may make it useful in ruling out the disease. We recommend that this test either be performed in conjunction with urine electrophoresis, immunofixation electro-phoresis and free light chain assay, or after biopsy confirming the diagnosis of myeloma.

Rib plasmacytoma and IgA multiple myeloma with hyperviscosity syndrome.

Solitary bone plasmacytoma (SPB) can progress to generalized myeloma if not treated early. The elderly population is increasing and delays in diagnosis of plasma cell malignancies are frequent among them. Hyperglobulinemia of multiple myeloma (MM) plays a role in hyperviscosity syndrome (HVS). A 65-year-old woman with hypertension and diabetes mellitus was admitted due to loss of appetite, muscle weakness, breathlessness and discrete expectoration, without fever. Chest X-ray showed an abnormal shadow projection on the right lung field, while computed tomography (CT) revealed an osteolytic mass at the sixth rib. There were more than 50% of plasma cells in the bone marrow samples and high IgA levels according to serum electrophoresis. Rib plasmacytoma and overt IgA-producing myeloma with HVS were diagnosed, but treatment was unsuccessful. Case studies may enhance the awareness about this ominous condition, which may develop unnoticed, particularly in elderly patients with renal insufficiency, and can pose difficulties with diagnosis in primary care settings.

Radiotherapy for solitary plasmacytoma of bone and soft tissue: outcomes and prognostic factors.

We investigated treatment outcomes of radiotherapy for solitary plasmacytoma (SP) and prognostic factors affecting survival. Between 1996 and 2010, a total of 38 patients were treated with radiotherapy for histologically proven plasmacytoma without evidence of multiple myeloma. Among these, 16 and 22 patients had SP originating from extramedullary soft tissue (EMP) and bone, respectively. Thirteen patients received adjuvant chemotherapy, and three patients underwent surgery prior to radiotherapy. At a median follow-up of 50 months (range, 8-142), radiotherapy demonstrated excellent local control (5- and 10-year local control rates, 81%). However, the 10-year multiple myeloma-free survival (MMFS) was 54% and the 10-year overall survival (OS) rates was 35%. Solitary bone plasmacytoma (SBP) more frequently progressed to multiple myeloma (MM) than EMP (10-year MMFS, 0% vs. 71%, p = 0.02). Radiotherapy with doses ≥40 Gy demonstrated better local control (10-year LC, 100% vs. 60%, p = 0.04) in SBP. In the multivariate analysis, elevated ß2-microglobulin was a significantly unfavorable prognostic factor affecting OS (p = 0.03). In conclusion, radiotherapy effectively treated SP without significant toxicity. However, progression to MM presents a challenging problem. Novel therapeutics are needed for patients with unfavorable prognostic factors.

[Plasmacytoid urothelial carcinoma of the bladder with prostate cancer: report of two cases]. / Variante plasmacytoïde de carcinome urothélial vésical et cancer prostatique : à propos de deux cas.

Plasmacytoid urothelial carcinoma (PUC) is a rare variant of urothelial carcinoma with aggressive clinicopathological behaviours. We experienced two cases of PUC of urinary bladder. Both cases were advanced cancer with extravesical invasion and lymph node metastases. They also had coexisting prostatic carcinoma, one was preoperatively diagnosed and the other was incidentally discovered after surgery. As these cases were the first report of PUC simultaneously associated with prostatic carcinoma, clinicopathological features and the treatment options were discussed.

Serum free light chain analysis in multiple myeloma and plasma cell dyscrasias.

After the development of a reliable method to detect free light chains in serum, several investigations have been conducted to explore their importance in plasma cell dyscrasias (PCD). Detection of monoclonal proteins is very important in the diagnosis and management of PCD, which include a broad spectrum of diseases such as multiple myeloma and also benign, premalignant disorders like monoclonal gammopathy of undetermined significance. The aim of this article is to summarize the recent studies and to highlight the importance of free light chain analysis in the diagnosis of PCD, its prognostic value and role in the management of this group of diseases.

[18F-FDG PET-CT in a case of solitary plasmacytoma of the soft palate]. / Tomografía por emisión de positrones con ¹8F-fluorodeoxy-glucosa en un caso de plasmocitoma solitario de paladar blando.

Solitary plasmacytoma is an uncommon tumor of plasma cells that can appear in the head and neck. It must be differentiated from multiple myeloma because of its initial presentation. A case of solitary plasmacytoma on the palate is presented. Furthermore, role of ¹8F-fluorodeoxyglucose Positron Emission Tomography (¹8F-FDG-PET) in its initial staging is analyzed.

Serum protein electrophoresis in 155 cats.

All serum protein electrophoresis (SPE) results obtained between 2002 and 2009 from clinical cases presented to the University of Bristol Feline Centre were examined retrospectively. One hundred and fifty-five results met the inclusion criteria. Signalment and final diagnoses were obtained from the case records. Clinical cases were classified as having normal or abnormal SPE results by comparison to reference intervals for SPE created using 77 clinically normal cats. Abnormal results were then further divided according to the specific SPE abnormality. Cases were also categorised, according to the final diagnosis, using the DAMNITV classification system. Of the 155 cases, 136 (87.7%) had abnormal SPE results, most commonly due to a polyclonal increase in gamma globulins. A monoclonal gammopathy occurred in four cats; one with feline infectious peritonitis (FIP), one with lymphoma and two cases of splenic plasmacytoma (one suspected, one confirmed). The most common DAMNITV classification associated with SPE abnormalities was infectious/inflammatory disease (80/136; 58.8%), including 39 cats diagnosed with FIP.