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.

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.

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.

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.

Serum free light chains in the diagnosis and monitoring of patients with plasma cell dyscrasias

Serum free light chain assay is a recently available test for diagnosis and monitoring of patients with plasma cell dyscrasias. In particular, this test is especially useful in patients that were previously difficult to follow with traditional laboratory methods. These patients include non-secretory multiple myeloma, amyloidosis and light chain deposition disease. In addition other uses for the test include monitoring response to treatment and earlier detection of relapse in all patients with plasma cell dyscrasias. Potential uses include assessing progression of patients with monoclonal gammopathy of undetermined significance, smoldering multiple myeloma, solitary bone plasmacytoma and extramedullary plasmacytoma to multiple meyloma. Analytical considerations for the assay are also discussed.

Seltene Ursache einer diffusen alveolären Hämorrhagie bei einem 45-Jährigen

Diffuse pulmonary hemorrhage denotes a diffuse bleeding into the alveoli as a result of severe damage of the alveolocapillary membrane. Autoimmune diseases, toxic injury and hemodynamic changes are the most frequent causes. A 45 year old male patient presented with diffuse alveolar hemorrhage. An Immunoglobulin A (IgA) paraprotein secreting myeloma was found to be the underlying cause. Immunohistochemistry revealed dense pericapillary and perivascular deposits of IgA, indicating a paraprotein mediated damage of the alveolocapillary membrane. The predominantly vascular pattern of damage was regarded as the most likely cause of the pulmonary hypertension in this patient. The diffuse pulmonary bleeding stopped after initiation of treatment consisting of vincristine, adriamycine and dexamethasone.

Nonsecretory plasma cell myeloma--becoming even more rare with serum free light-chain assay: a brief review

CONTEXT

Nonsecretory plasma cell myeloma is characterized by an absence of detectable monoclonal protein in both the serum and urine. It is generally reported to comprise approximately 1% to 5% of all cases of plasma cell myeloma and, because of its rarity, requires a high index of suspicion and bone marrow biopsy to establish the diagnosis.

OBJECTIVE

Review the diagnostic strategy when nonsecretory plasma cell myeloma is a clinical consideration in light of a relatively new serum free light chain assay.

DATA SOURCES

Case study and review of the literature.

CONCLUSIONS

Initial data using a recently developed nephelometric serum free light chain assay suggests that only about one fourth of nonsecretory plasma cell myeloma cases may be truly nonsecretory. The definition of nonsecretory plasma cell myeloma should be modified to exclude cases with evidence of clonality using the serum free light chain assay.

[Soluble syndecan-1 levels in different plasma cell dyscrasias]

INTRODUCTION

Syndecans are a family of cell surface proteoglycans. In the bone marrow of multiple myeloma patients syndecan-1 is expressed only on the surface of malignant plasma cells. The aim of the study was to determine the soluble syndecan-1 levels in different plasma cell dyscrasias.

METHODS

The serum concentration of soluble syndecan-1 was measured using human syndecan-1 enzyme-linked immunosorbent assay kit.

RESULTS

Patients with multiple myeloma showed a significantly higher median serum syndecan-1 level than patients with plasmocytoma or monoclonal gammopathy of undetermined significance. Statistically significant differences were also observed among Salmon-Durie subgroups of 50 patients suffering from multiple myeloma. In addition to these findings a statistical correlation with other independent prognostic factors such as serum beta2-microglobulin level, monoclonal immunoglobulin concentration, and bone marrow plasma cell count could also be noted. A significant decrease in median serum syndecan level was observed in patients who responded to chemotherapy, whereas no change in the median syndecan-1 level could be observed in nonresponders.

CONCLUSION

These findings confirm the observation that high serum soluble syndecan-1 level is associated with a more advanced disease stage and is a strong independent indicator of poor prognosis. A diminished serum syndecan-1 reading as a result of chemotherapy may be a good indicator of favorable response to antitumor treatment.

Response to thalidomide in multiple myeloma: impact of angiogenic factors

Thalidomide has antiangiogenic and immunomodulatory effects, mediated by several cytokines such as vascular endothelial growth factor (VEGF), fibroblastic growth factor (FGF-2), hepatocyte growth factor (HGF), interleukin-6 (IL-6) and tumor necrosis factor-alpha (TNF-alpha). Although extramedullary plasmacytomas (EMP) have a high vascularization, the response of these patients to thalidomide is controversial. Thirty-eight patients with refractory/relapsed MM were treated with thalidomide. Eleven patients had EMP when therapy was initiated. Serum specimens were obtained in patients before treatment was started and at the time of maximum response in responding patients or at thalidomide discontinuation in non-responders. Serum levels of VEGF, HGF and FGF-2 were determined in 18 patients whereas IL-6 and TNF-alpha were measured in 19 patients. Sixteen of the 38 patients (42%) responded to thalidomide. The response rate was significantly higher in patients without EMP (59% vs 0%, p = 0.0006 ). VEGF serum levels were significantly higher in responding patients. In contrast, baseline serum levels of HGF were significantly lower in responders. Neither VEGF nor HGF serum levels showed correlation with the presence of EMP. Baseline TNF-alpha serum levels were significantly lower in responding patients and in those without EMP. The serum levels of FGF-2 and IL-6 did not correlate with response to treatment or presence of EMP.

Prognostic value of angiogenesis in solitary bone plasmacytoma

Angiogenesis plays an important role in the biology of multiple myeloma (MM) and has prognostic importance in this disease. Solitary plasmacytoma is a localized plasma cell malignancy that progresses to MM in a significant number of patients. We examined if angiogenesis is increased in solitary plasmacytoma and if it can help identify patients likely to progress to myeloma. We studied angiogenesis in plasmacytoma biopsy samples and bone marrow biopsies from 25 patients. High-grade angiogenesis was present in 64% of plasmacytomas. In contrast, bone marrow angiogenesis was low in all patients. Patients with high-grade angiogenesis in the plasmacytoma sample were more likely to progress to myeloma and had a shorter progression-free survival compared with patients with low-grade angiogenesis (P =.02). Angiogenesis is increased in solitary plasmacytoma and is a significant predictor of progression to myeloma and provides further evidence of its importance in the pathogenesis of myeloma.

Clinical significance of vascular endothelial growth factor and hepatocyte growth factor in multiple myeloma

Angiogenesis is a crucial process in the progression of multiple myeloma (MM). Vascular endothelial growth factor (VEGF) and hepatocyte growth factor (HGF) are multifunctional cytokines that potently stimulate angiogenesis including tumour neovascularization. Serum levels of VEGF and HGF were measured in 52 patients with MM by enzyme-linked immunosorbent assay (ELISA). Serum levels of VEGF and HGF were elevated in MM patients compared with healthy controls (VEGF: mean 0.31 ng/ml and 0.08 ng/ml respectively, P < 0.01; HGF: mean 2.17 ng/ml and 0.45 ng/ml, respectively, P < 0.001). In serial samples taken after chemotherapy, serum VEGF and HGF levels were correlated with M-protein levels. Serum levels of VEGF were higher in patients with extramedullary plasmacytomas than in patients without them (P < 0.05). They were also significantly higher in a group of patients who showed poor response to chemotherapy (P < 0.01). Serum levels of HGF were higher in patients with complications such as anaemia, hypercalcaemia and amyloidosis than in patients without these complications (P < 0.01, P < 0.05, P < 0.05 respectively). Both serum VEGF and HGF levels were significant predictors of mortality (P = 0.01, P = 0.02, respectively, log-rank test). The present study demonstrated that serum levels of VEGF and HGF are significantly elevated and dependent on the severity of MM, suggesting that measurement of VEGF and HGF may be useful for assessing disease progression and for predicting the response to chemotherapy in MM patients.

Evaluation of hemorheological risk factor profile in plasmacytoma patients

The hemorheological parameters, plasma viscosity, hematocrit, erythrocyte aggregation and deformability of blood samples obtained from plasmacytoma patients are measured by capillary viscometer, microcentrifuge, Myrenne aggregometer, and filtrometer, respectively. These parameters are significantly altered in patients compared to those of normal subjects. The plasma viscosity and erythrocyte aggregation are increased, whereas erythrocyte deformability and hematocrit are decreased. Based on these parameters the hemorheological risk factor profiles are developed and by their overall risk factors, the patients with low and high risk factors are identified.

Nodal plasmacytoma with significant paraproteinaemia

We present a case of primary nodal plasmacytoma in an elderly Chinese woman that was associated with significant paraproteinaemia and paraproteinuria. Clinical and laboratory features of the patient satisfied Durie's criteria for the diagnosis of multiple myeloma. The present case was unusual in two aspects. Firstly, there was no evidence of clonal plasma cell proliferation elsewhere in the body after extensive radiological investigations, repeated bone marrow examinations, and polymerase chain reaction for immunoglobulin gene rearrangement study. Secondly, the clinical behaviour was indolent despite the large amount of paraprotein production, and showed satisfactory disease control with local radiotherapy. The differential diagnoses of plasmacytosis in the lymph node are also discussed.

A prospective study of CD38/45 flow cytometry and immunofluorescence microscopy to detect blood plasma cells in patients with plasma cell proliferative disorders

Malignant plasma cells can be detected in the blood of patients with multiple myeloma (MM) using flow cytometry (FC), immunofluorescence microscopy (IM), or a variety of molecular techniques. Increased numbers of light chain-restricted blood plasma cells as detected by IM is associated with a diagnosis of overt MM and a decreased overall survival. The IM technique is time consuming; therefore, a prospective study was designed to test whether CD38 CD45 FC could simplify the procedure. Blood samples from 769 patients with plasma cell proliferative disorders were studied prospectively by FC and IM over a one-year period. The FC technique was performed on 1 ml of whole blood after ammonium chloride red blood cell lysis and utilized anti-CD38PE and anti-CD45PerCP. The number of CD38+ 45- events were enumerated and compared to the number of light chain-restricted plasma cells detected by the standard IM technique. In 46% (353/769) of cases > or = 1 CD38+ CD45- events were detected by FC whereas IM was positive for light chain restricted plasma cells in 33%; there was concordance between FC and IM in 73% of cases. In 20% of cases FC was positive and IM was negative; however, in 7% of cases FC was negative yet light chain-restricted plasma cells were detected by IM. FC was positive in 88% (134/153) of cases where the IM technique showed a high number of circulating plasma cells. This study demonstrates that two-color CD38/45 FC identifies most cases with a high IM result and reduces the workload in the clinical laboratory. The prognostic implications of a positive FC screen but a negative IM will require long-term patient follow-up.

Defensins are dominant HLA-DR-associated self-peptides from CD34(-) peripheral blood mononuclear cells of different tumor patients (plasmacytoma, chronic myeloid leukemia)

The HLA-DR-associated peptides from peripheral blood mononuclear cells of 2 patients with plasmacytoma and 1 with chronic myeloid leukemia were isolated, identified, and compared. Several were identified as derivatives of the defensin family. Defensins (or human neutrophil peptides [HNP]) are antimicrobial, cationic peptides of 29 to 35 amino acids in length and are the major constituents of the azurophilic granules of human neutrophils. Using peripheral blood cells from leukapheresis, containing about 90% of polymorphonuclear cells, we could identify HNP-1, -2, and -4 and propeptides of up to 49 amino acids in length, eluted from HLA class II molecules. Binding of isolated and synthetic defensin peptides to various HLA-DR alleles using an in vitro binding/competition assay based on size exclusion chromatography revealed that defensin may bind into the peptide-binding groove. In a T-cell competition assay, defensins were able to reduce the proliferation of an HLA-DR-restricted T-cell line after preincubation of stimulating cells (CHO-DRB1*0401 transfectants) with defensin. Therefore, binding of defensins might prevent T-cell recognition of HLA class II molecules expressed on different blood precursor cells (all of which are "nonprofessional" antigen-presenting cells) by blocking the HLA peptide-binding groove or, alternatively, might protect defensin-expressing cells from self-destruction. (Blood. 2000;95:2890-2896)

[IL-6, p53 and proto-oncogene c-myc play different roles as biological markers of plasma cell dyscrasias]

PURPOSE

To determine the role of serum levels of IL-6 and p53 mutant protein as well as of c-myc proto-oncogene alterations: a) in discriminating between benign (MGUS) and malignant Plasma cell dyscrasias (Multiple and Microsecreting Myeloma, Plasmocytoma); b) in monitoring the clinical course of malignant forms of this disease.

PATIENTS AND METHODS

Eighty-eight patients affected by Plasma cell dyscrasias (58 MGUS, 24 MM and 6 PLC) entered this study. Using commercially available ELISA kits, serum levels of IL-6 and p53 have been determined in all the patients. In addition, a selected group of patients (n = 30) was also analyzed for structural c-myc gene alterations by Southern blot technique.

RESULTS

The results show that, conversely from p53 protein, IL-6 and c-myc gene may represent useful diagnostic markers for discriminating benign from malignant forms of Plasma cell dyscrasia. On the contrary, preliminary findings of the same work indicate a potential role for the mutant p53 protein in monitoring the response to chemotherapy of patients affected by MM or PLM.

CONCLUSIONS

Overall, these data suggest that the combined use of IL-6, p53 and c-myc may provide a new approach for a more rational management of Plasma cell dyscrasia patients.

Coexistence of erythrocyte agglutination and EDTA-dependent platelet clumping in a patient with thymoma and plasmocytoma

For 8 years, EDTA-dependent pseudothrombocytopenia was observed in a 55-year-old woman with a history of rheumatoid arthritis who had undergone surgery for lymphoepithelial thymoma 11 years earlier. The clinical picture was characterized by the presence of platelet clumps and antiplatelet antibodies of the IgM class. With the recent appearance of a solitary extramedullary plasmocytoma in the right retrobulbar region and the detection of an IgGlambda monoclonal gammopathy, blood examination also revealed erythrocyte agglutinates alongside the platelet clumps and the presence of a cold IgG antibody with antiI specificity. Both phenomena were observed in vitro when the sample temperature declined to 20 degrees C to 25 degrees C, but not at 37 degrees C. While the EDTA-dependent antiplatelet antibodies did not appear to be chronologically correlated with the patient's diseases, the cold antierythrocyte autoantibodies were strictly related to the plasmocytoma and the IgGlambda monoclonal component in serum. To our knowledge, this is the first description of an association between EDTA-dependent platelet and erythrocyte agglutinates, with a clinical picture of pseudothrombocytopenia and pseudoerythrocytopenia due to cold agglutinins.

Solitary bone plasmacytoma: outcome and prognostic factors following radiotherapy

PURPOSE

To clarify the natural history of solitary plasmacytoma of bone (SBP) after radiation treatment.

METHODS AND MATERIALS

Between 1965-1996, we identified 57 previously untreated patients with a SBP. A serum myeloma protein was present in 33 patients (58%) and Bence Jones proteinuria was present in an additional eight patients (14%). The median radiotherapy dose was 50 Gy (range, 30-70 Gy). Overall survival, cause-specific survival, and freedom from progression to multiple myeloma were calculated actuarially.

RESULTS

Local control was achieved in 55 of 57 patients (96%). For those 29 patients (51%) who subsequently developed multiple myeloma, the median time to progression was 1.8 years. There was a direct correlation between persistence of abnormal protein following radiotherapy and the likelihood of developing multiple myeloma. Among 11 patients with disappearance of myeloma protein, only two developed multiple myeloma after 4 and 12 years, in contrast to progression in 57% of patients with a persistent protein peak and 63 % of those with nonsecretory disease (p = 0.02). Among 23 patients with thoracolumbar spine disease, 7 of 8 patients staged with plain radiographs alone developed multiple myeloma in comparison with 1 of 7 patients who also had magnetic resonance imaging (MRI) (p = 0.08). For all patients, the median survival from radiotherapy was 11.0 years. The median cause-specific survival of patients with disappearance of myeloma protein was significantly longer than that of the remaining patients (p = 0.004).

CONCLUSION

Results supported the importance of precise staging that includes MRI of the spine for optimum patient selection and the application of definitive radiotherapy. Those patients with myeloma protein that disappears following radiotherapy represent a category with a high likelihood of cure.

Coexisting primary early gastric plasmacytoma and sarcoidosis with hypercalcaemia

We report on a 61-year-old woman with coexisting early stage primary gastric plasmacytoma and sarcoidosis with hypercalcaemia. Laboratory data on admission showed hypercalcaemia, with 12.8 mg/dl, parathyroid hormone-related peptide (PTHrP) 1.2 pmol/l, C-PTHrP 69.5 pmol/l, and 1,25-dihydroxyvitamin D3 46.7 pg/ml. Neoplastic plasma cells proliferated in the propria mucosa of the stomach, showed a monoclonal immunoglobulin of cytoplasmic IgA (lambda light chain) and were positive for leucocyte common antigen and epithelial membrane antigen on paraffin section prepared from a stomach biopsy specimen. Russel bodies were present, as were crystals. Abundant sarcoid granulomas were observed in many of the regional lymph nodes around the stomach and in the dermis of a skin nodule. The patient underwent subtotal gastrectomy with administration of antimyeloma chemotherapy. We suggest that the hypercalcaemia in this patient was due to PTHrP production by neoplastic plasma cells.

Increased plasma interleukin-6 in cutaneous plasmacytoma: the effect of intralesional steroid therapy

Cutaneous plasmacytosis is a rare disorder without systemic plasma cell proliferation in organs other than the skin, with a possible malignant transformation. However, there are few effective therapies available. It has been reported that interleukin-6 (IL-6), which is a cytokine inducing B-cell differentiation to immunoglobulin-producing cells, plays a part in systemic plasmacytosis. In this study, we performed intralesional steroid therapy in the lesions of cutaneous plasmacytosis in three patients, which resulted in sufficient clinical effects. We demonstrated that before treatment, plasma IL-6 levels were significantly elevated in all the patients, and that levels were reduced in parallel with the clinical improvement after therapy. Immunohistochemistry revealed IL-6 protein expression on tumour cells in the lesional skin. Reverse transcription-polymerase chain reaction (RT-PCR) detected IL-6 mRNA in the lesional skin in all cases, levels of which were decreased after the effective intralesional steroid therapy, but which were unchanged after ineffective topical photochemotherapy (PUVA). Peripheral blood mononuclear cells from the patients produced significantly large quantities of IL-6 which were reduced by addition of steroid in vitro. These results suggest that the generation of IL-6 plays the key role in cutaneous plasmacytosis and that intralesional steroid therapy is effective in reducing the production of IL-6 in this disorder.

Increased serum CA125 levels in plasma cell dyscrasias

We report 2 cases of plasma cell dyscrasia presenting with significantly elevated serum CA125 levels. The serum levels of CA125 from these patients correlated well with their serum M-protein levels. One patient had an IgG-kappa type extramedullary plasmacytoma with the culture supernatant from lymph node plasma cells showing a considerably high level of CA125 activity. The serum IgG fraction purified using a protein A column was devoid of any detectable CA125 activity, negating that the serum IgG M-protein from this patient might respond with a false-positive result in the CA125 immunoradiometric assay. The other patient had an IgG-lambda type plasma cell leukemia with the culture supernatant from peripheral mononuclear cells also showing a high level of CA125 activity. These observations may suggest that in plasma cell dyscrasias the CA125 antigen is spontaneously produced by tumor cells.

Extramedullary plasmacytoma of the jejunum

A case of extramedullary plasmacytoma (EMP) of the jejunum, an uncommon neoplasia, is reported. A 56-year-old Japanese woman who experienced intermittent upper abdominal pain and weight loss had a large movable mass in the upper abdomen. The mass was hypervascular in an angiographic study and positive for gallium-67 citrate scintigraphy. Immunoelectrophoresis showed the presence of an M-component of immunoglobulin (Ig) A-lambda in the serum. It was identified as an EMP immunohistochemically positive for IgA-lambda. This M-component disappeared after resection and chemotherapy. The clinical features of this rare neoplastic disorder are discussed.

Serum neural cell adhesion molecule in multiple myeloma and other plasma cell disorders

Serum embryonic neural cell adhesion molecule (eNCAM) levels were measured at diagnosis in 92 patients with plasma cell disorders. Significantly elevated levels of serum eNCAM were detected in patients with multiple myeloma when compared to both normal controls and patients with monoclonal gammopathy of uncertain significance (MGUS). Very high levels of serum eNCAM were seen in patients with high tumour burdens. There was a significant correlation between serum eNCAM and beta 2-microglobulin (beta 2m) (r = 0.33; P = 0.002), but not between serum eNCAM and C-reactive protein or serum albumen. There was a trend towards longer survival for patients with low serum NCAM. The median survival of the low serum eNCAM group (eNCAM < 20 U/ml) was 36 months compared to 16 months for the high serum eNCAM group (log rank test chi 2 = 2.42, P = 0.1). Serum eNCAM is a new marker of tumour mass in multiple myeloma and correlates with clinical stage and beta 2m. Patients with low serum eNCAM levels may have a survival advantage. Serum eNCAM warrants further evaluation as a tumour marker and prognostic factor in multiple myeloma.

Increase of monocytes predicts mobilization of peripheral stem and progenitor cells after chemotherapy followed by G-CSF administration

Mobilization of primitive haematopoietic cells to the peripheral blood was studied in 25 patients with haematological malignancies. The optimal level of peripheral stem cells (PSC), defined by their surface expression of CD34, was significantly higher after mobilization with G-CSF, either following chemotherapy or alone (median: 123 x 10(6)/l and 143 x 10(6)/l of CD34+ cells respectively) than without administration of G-CSF subsequent to chemotherapy (median: 27 x 10(6)/l of CD34+ cells). An individual variation in when optimal mobilization of CD34+ cells and myeloid progenitors occurs after chemotherapy and G-CSF administration was noted (median: day 12, range 7-24 days), which makes it difficult to predict when PSC collections in a given patient should be performed. In this study, chemotherapy followed by G-CSF administration resulted in a short lasting (2-3 days) peak appearance of CD34+ cells that could predicted by a 2-fold increase in absolute numbers of monocytes, as compared to the previous day. After the peak level of CD34+ cells in the blood was reached, no further increase in monocytes was seen. The identification of an increase in monocytes, to be used as a predictive variable for when optimal mobilization of PSC will occur in a given patient, may be particularly useful in the individual timing of PSC collections from non-hospitalized patients.

Determination of IL6, IL1, and IL4 in the plasma of patients with multiple myeloma

Interleukin 6 (IL6) plasma levels were measured in 63 patients with multiple myeloma and 8 individuals with benign monoclonal gammopathy. 15 of these 71 samples showed by an enzyme linked immunosorbent assay (ELISA) detectable levels that ranged from 5 to 107 pg of IL6/ml. The IL6 levels of patients with multiple myeloma did not differ significantly from those of normal individuals (N = 25, range 5-27 pg IL6/ml) (Student's t-test, p = 0.295). The samples were negative for IL4; 3 were found positive for IL1 beta. A correlation between IL6, IL4 and IL1 beta levels and disease status was not observed for this group of patients.

The increase of CD5LOW+NK cells in patients with multiple myeloma and plasmacytoma

CD5 antigen is present on all normal alpha beta T cells and some B cells. Human NK cells do not usually express CD5 antigen, but we found a novel subset of CD5LOW (low density of CD5) positive (CD5LOW+) natural killer cells (NK cells) in patients with multiple myeloma (MM) and plasmacytoma. To detect CD5LOW+NK cells, we examined the lymphocytes of 23 patients with MM and plasmacytoma by flow cytometry. Five out of 23 patients had CD5LOW+NK populations. These patients had many more NK cells than the other patients in the peripheral blood and bone marrow. The CD5LOW+NK cells had CD2, low density of CD8, CD16 and CD56, but no CD3, CD19, or CD20. Most of the CD5LOW+NK cells had HLA-DR, unlike the CD5-NK cells. Sorted CD5LOW+CD16+ populations were large granular lymphocytes (LGL). The CD5LOW+NK cells had some lytic activity on K562 cells in a 4-hour 51Cr release assay. Our results indicate that there is a novel subset of NK cells in some patients with MM and plasmacytoma and that CD5LOW+NK cells may be associated with NK cell activation.

Mutational activation of N- and K-ras oncogenes in plasma cell dyscrasias

The frequency of N- and K-ras oncogene mutations was investigated in plasma cell dyscrasias. Genomic DNAs from 128 patients were selected for this study: 30 monoclonal gammopathies of undetermined significance, 8 solitary plasmacytomas, 77 multiple myelomas (MM), and 13 plasma cell leukemias (PCL). A two-step experimental approach was devised. All samples were screened for mutations by single-strand conformation polymorphism analysis. DNA fragments displaying an altered electrophoretic mobility were further studied by direct sequencing to confirm and characterize the nature of the mutations. Ras mutations are not randomly distributed because they are detectable only in MM (9%) and PCL (30.7%). N-ras codons 12, 13, and 61 and K-ras codon 12 were found to be mutated, but N-ras codon 61 mutation was the most frequent finding (63.6%). In conclusion, ras mutations were found in PCL, and in a subset of MM characterized by advanced-stage disease and adverse prognostic parameters. Furthermore, based on our findings, it is possible to speculate that ras mutations represent a late molecular lesion in the process of multistep carcinogenesis.

Extramedullary plasmacytoma of the soft palate

A 59-year-old white male presented with symptoms of an upper respiratory infection and the sensation of nasal fullness or obstruction. There were no constitutional symptoms or history of previous oropharyngeal neoplasms. Examination revealed a fleshy tan-pink 2 cm. x 1 cm. pedunculated lesion at the base of the uvula posteriorly, extending into the posterior soft palate. Indirect laryngoscopy confirmed extension of the lesion base onto the posterior soft palate. There was no palpable cervical adenopathy. CT scan of the sinuses and neck revealed no abnormality except the soft tissue mass in the area of the uvula and soft palate. Excisional biopsy of the lesion revealed a plasmacytoma which produced a monoclonal lambda chain immunoglobulin. Hemoglobin was 17.2 g/d. Serum electrophoresis and immunophoresis, Bence-Jones protein, bone marrow, and bone scan were normal. Twenty-six months later, a 1.5 cm. pedunculated lesion was noted at the site of original tumor, which was demonstrated to be recurrent plasmacytoma on excisional biopsy. No other lesions were identified on direct laryngoscopy and skeletal survey was normal. Repeat laboratory studies were normal except for a slight hypergammaglobulinemia (total protein 6.4 g/d., albumin 51.5 percent, alpha 1 globulin 4.0 percent, alpha 2 globulin 11.4 percent, beta globulin 12.8 percent, and gamma globulin 20.2 percent). The patient refused further treatment and has had no further recurrences at one year.

Lectin histochemistry of human bone marrow: investigation of trephine biopsy specimens in normal and reactive states and neoplastic disorders

The lectin binding pattern of bone marrow cells in normal and reactive states and in various neoplastic disorders was investigated using trephine biopsy specimens taken from the iliac crest. The tissue samples were routinely processed (fixed in formalin and embedded in paraffin wax) and subjected to mild decalcification with EDTA. The following results were obtained. (1) More than half of the 23 fluoresceinated lectins used reacted with normal blood cells and/or their neoplastic derivatives. Inhibition tests with the appropriate sugars confirmed the specificity of binding for the majority, but not all, of the lectins. (2) WGA, Con A, PSA, STA and RCA60 and RCA120 produced a particularly intense reaction with normal, reactive and neoplastic myeloid cells. Erythroblasts exhibited weak staining in a few cases by a few lectins (WGA producing the strongest staining), while megakaryocytes nearly always remained unstained. Neoplastic lymphoid cells in various lymphoproliferative disorders and plasmacytoma cells generally reacted with the same lectins as the myeloid cells. (3) Since neoplastic myeloid cells in various myelodysplastic and myeloproliferative disorders exhibited a lectin binding pattern similar to that of myeloid cells in normal and reactive bone marrow, it is unlikely that lectin histochemistry of the bone marrow will prove of great value in the diagnosis of myelodysplastic-myeloproliferative disorders.

[Solitary plasmacytoma. A retrospective analysis of 15 cases]

Solitary plasmocytoma is a rare plasma cell disorder as compared with multiple myeloma. In order to evaluate their relationships, the clinical findings in 51 patients with solitary plasmocytoma were analyzed. The median follow-up was 7.8 years (range 3 to 14). Twenty patients (39%) developed multiple myeloma in a average of 3.8 years. The risk factors associated with the development of multiple myeloma were an initial abnormal electrophoresis (M peak), age (less than 40 years) and an increase in beta-2-microglobulin. Although radiotherapy remains the initial treatment of solitary plasmocytoma, a careful evaluation should be performed in order to consider chemotherapy in selected patients with high risk of developing multiple myeloma.

[Hemorheological and coagulation aspects in plasmacytoma]

We reported the main rheological and coagulative features in seven patients affected with monoclonal gammapathy: four of them presented IgA class paraprotein, two IgM class paraprotein and one IgG class paraprotein. All presented increased plasma and serum viscosity. The four patients affected with IgA monoclonal paraproteinaemia underwent one plasma volume plasmapheresis. This procedure has been demonstrated to be useful and effective in reducing both plasma and serum viscosity.

Thyroid plasmacytoma with dermatomyositis and palmar fasciitis

A 74-year-old woman with a primary thyroid plasmacytoma was studied. Clinical signs included a mass in the neck, as well as muscle and skin involvement due to dermatomyositis. In her serum a monoclonal IgG lambda was present. Immunohistochemistry showed an intracellular monoclonal IgG lambda component. After thyroid surgery and radiation, clinical improvement and fall of M protein were noted. On longterm followup, only palmar fasciitis persisted.

[Solitary plasmacytomas in the head area. Diagnostic and therapeutic considerations]

Based on two case reports the inherent problems of diagnosis and treatment of this rare tumor are discussed. The importance of a complex immunohistologic and immunochemical analysis of the monoclonal immunoglobulin produced by the tumor is emphasized. Determining the serum level of the immunoglobulin is decisive for establishing the necessary treatment strategy. Apart from the tumor-specific aftercare by a specialist, these patients always require additional treatment at an immunology clinic.

Immunological and functional determination of the protease inhibitors, protein C and antithrombin III, in liver cirrhosis and in neoplasia

Using a new rapid coagulant method, protein C activity (PC act) was determined in liver cirrhosis and malignancies and compared with PC antigen and AT III values. PC was decreased in a more pronounced manner than AT III in liver cirrhosis, mainly due to impaired synthesis. This is of special clinical interest because PC proved to be a high sensible indicator of liver cell dysfunction. Decreased levels of PC act (PC ratio act/ag less than 1) in decompensated liver cirrhosis may be caused by the synthesis of dysfunctional PC and/or vitamin K deficiency with production of undercarboxylated PC most sensitively registered by this coagulant assay. An increased clearance of in vivo activated PC induced by DIC may play an insignificant role. In patients with liver metastases, PC act (but not AT III and immunological parameters) was significantly reduced, supporting the conclusion that in these patients liver dysfunction concomitant with synthesis of dysfunctional PC must be discussed as the main cause of this alteration.

Long-term study of gammopathies. Clinically benign cases showing transition to malignant plasmacytomas after long periods of observation

Since 1968, our Clinical Chemistry laboratory has been performing protein electrophoresis on sera of patients with total protein levels of over 85.0 g/L and under 55.0 g/L. Monoclonal gammopathies were found in 534 cases. Immunoelectrophoresis was carried out using antisera to the heavy chains gamma, alpha, mu, delta, and epsilon, and to the light chains kappa and lambda. Urine from these patients was tested for Bence-Jones protein. Records and smears, when available, were examined for clinical or hematologic evidence of multiple myeloma and other lymphoid malignancies. Sixty-five percent of these 534 cases were referred to the laboratory with a provisional diagnosis of plasmacytoma but 35% were not clinically suspected. Twenty-two cases with gammopathy, but no clinical or hematologic symptoms of plasma cell dyscrasia, were selected and followed up. Eight of these patients (36%) had converted to malignancy by the end of ten years. These results show the value of screening for abnormal proteins and the need for a long-term follow-up in such patients, prior to diagnosis of plasma cell dyscrasia.

The potential value of immuno-isoelectric focusing in the diagnosis and management of solitary plasmacytoma

Immuno-isoelectric focusing is a highly sensitive method of detecting small quantities of monoclonal protein. We have previously reported the first demonstration of serum paraprotein in non-secretory myeloma using this technique (Sheehan et al. 1985). We now report a case of solitary plasmacytoma where this technique revealed a small concentration of serum paraprotein when conventional techniques failed, and discuss the potential value of focusing in plasma cell dyscrasia, with limited tumor cell mass. focusing in plasma cell dyscrasia, with limited tumour cell mass.

The Crow-Fukase syndrome: a study of 102 cases in Japan

Clinical manifestations of 102 cases with the Crow- Fukase syndrome (the syndrome of polyneuropathy, anasarca, skin changes, endocrinopathy, dysglobulinemia, and organomegaly), with or without myeloma, were reviewed. Fifty-six cases with myeloma consisted of 31 with osteosclerotic, 17 with mixed osteosclerotic and osteolytic, and 8 with osteolytic. Forty-six cases without myeloma consisted of 2 with extramedullary plasmacytoma, 33 with M protein alone, and 11 with polyclonal protein alone. There was no significant difference in incidence of the major clinical manifestations between the two groups with and without myeloma. They had a common characteristic histologic finding of the lymph node resembling that of Castleman's disease.