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The detection and quantification of immunoglobulin free light chains in serum and urine is recommended for the diagnosis and monitoring of monoclonal gammopathies according to the guidelines of the International Myeloma Working Group (IMWG). Several tests are currently available in the clinical laboratory to detect and quantify free light chains but although quality, efficiency, and effectiveness have been improved, the results are still variable and poorly harmonized and standardized. The present review article wants to analyze these aspects, with a keen eye on techniques, such as mass spectrometry, that could replace in the practical clinical laboratory the current methods including Bence-Jones protein assay and free light chain immunoassays., (Copyright © 2021 The Canadian Society of Clinical Chemists. Published by Elsevier Inc. All rights reserved.)

Background: Serum free light chain (FLC) analysis with ratio and urine immunofixation electrophoresis (IFE) are both available for routine use in helping to detect plasma cell dyscrasia and related diseases., Cases: Case reports showing one serum positive for serum FLC but that showed a hook effect and overestimated the amount of monoclonal FLC while urine IFE was negative for Bence Jones protein, and a second serum that showed elevated FLC κ and λ but a normal κ/λ ratio, while urine IFE was positive for Bence Jones protein., Conclusions: These two techniques complement one another. Neither of the techniques is truly quantitative, and both exhibit methodological defects.

The paper describes a clinical case of a female woman with nephropathy due to light chain deposition disease caused by secretion of κ Bence-Jones protein. Complete immunochemical remission was achieved after induction therapy using a bortezomib + cyclophosphamide + dexamethasone regimen. Renal function remained unchanged (glomerular filtration rate 16 ml/min), there was a reduction in proteinuria from 5.8 to 2.6 g/day. High-dose melphalan (200 mg/m2) chemotherapy with peripheral blood stem cell autotransplantation was performed as consolidation of remission. A year posttransplantation, there was no secretion of κ light chains; however, monoclonal IgG lambda emerged in a quantity of 3.2 g/l. At the same period, nephrotic syndrome became progressive (daily proteinuria 12 g) and dialysis-dependent renal failure developed. A repeat renal biopsy specimen revealed changes, suggesting that there was a decrease in renal deposits of κ light chains. Simultaneously with this, the obvious negative trend as progressive nephrosclerosis and fixation of IgG and λ light chains in the glomeruli (in the sclerotic areas) cause IgGλ monoclonal protein to be involved in the genesis of further kidney injury. Attention is also paid to different characteristics of capillary wall deposits by density (according to the electron microscopic findings), which may point to their different qualitative composition and possibly different formation duration. Papaprotein Gλ disappeared after a year without therapy, suggesting its reactivity. The findings confirm that worse renal function is caused by the action of paraprotein Gλ due to secondary (after autologous hematopoietic stem cells transplantation) monoclonal gammopathy.

A 60-year-old man, who had been treated for chronic kidney disease and chronic hepatitis B infection, was referred to our hospital following presentation with thoracic bone pain and exacerbation of proteinuria and hematu- ria. On admission, laboratory test results showed evidence of hypophosphatemia, glucosuria and elevated levels of both urinary NAG and 62MG.The patient was diagnosed with Fanconi syndrome based on findings indicating the presence of pan-aminoaciduria, elevated urinary excretion of uric acid and an increased phosphorus reabsorption rate. Furthermore, bone scintigraphy showed increased multiple symmetric uptake of radiotracer in both sides of the ribs, leading to the diagnosis"of hypoposphatemia-related osteomalacia with renal Fanconi syndrome. Urinary immunoelectrophoresis indicated the presence of K Bence Jones' protein (BJP). A bone marrow biopsy examina- tion showed that the plasma-to-cell ratio was less than 10%. However, the patient had over lg/day of proteinuria and suppression of serum IgM (18mg/dL) and was, therefore, diagnosed with multiple myeloma based on SWOG criteria. Light microscopic examination showed evidence of glomerulosclerosis, intimal thickness of interlobular arteries and acidophilic granular deposits in the cytoplasm of the proximal epithelial tubular cells. Immunofluores- cence indicated positive anti-K staining in these regions. Electron microscopic examination of the proximal tubular epithelial cells revealed the presence of numerous diamond-shaped and oval crystals, thought to be the K light chain of BJP. In general, cast nephropathy, light chain deposition disease (LCDD) and AL amyloidosis are recog- nized renal injuries caused by myeloma. However, there have been few clinical reports of Fanconi syndrome with multiple myeloma, such as the case study we have described here. In addition, histological examination of a biopsy sample provided further evidence of K BJP in the proximal epithelial tubular cells.

A 51-year-old man was admitted to our hospital complaining of right upper quadrant abdominal and back pain. Severe hepatomegaly (six fingerbreadths) was detected by liver palpation. Blood test results showed cholestatic liver disease. He was diagnosed with amyloidosis by liver biopsy. Bone marrow aspiration revealed 15% of contents to be plasma cells. BJPκ was detected by urine electrophoresis. Therefore, he was diagnosed with the BJPκ type of multiple myeloma with systemic amyloidosis. The patient was treated with bortezomib, dexamethasone and high-dose melphalan with autologous peripheral blood stem cell transplantation. He achieved VGPR (very good partial response) after transplantation. Hepatomegaly improved but swelling persisted, and he was therefore treated with 1.3 mg/m(2)/day of bortezomib and 20 mg/day of dexamethasone on day 1 and day 15 in 28-day cycles. Upon finishing 22 cycles in June 2014, his liver had returned to normal size. Restoration of normal liver size after treatment is rare in cases with severe hepatomegaly due to systemic amyloidosis. We thus report our case with a review of the relevant literature.

Tubular intraluminal inflammatory cells may be seen in kidney biopsies of patients with pyelonephritis, cell-mediated transplant rejection, autoimmune tubulointerstitial nephritis, allergic reactions, or in association with monoclonal light chain casts. When casts in a native kidney are primarily composed of granulocytes, the cause is most commonly acute pyelonephritis due to an ascending bacterial urinary tract infection. We report a 57-year-old man with acute kidney injury and an intense intraluminal neutrophil response to monoclonal lambda light chain crystal containing casts.

Multiple Myeloma has been recognized since Ancient Times. The first well-documented case was reported in 1844 by Samuel Solly. The most commonly recognized case is that of Thomas Alexander McBean, a highly respectable tradesman from London in 1850. Mr. McBean excreted a large amount of protein that was described by Henry Bence Jones in the middle of the 19th century. Jones was a well-known physician and made many contributions to medicine. One of the best known cases of multiple myeloma was that of Dr. Loos that was reported by Otto Kahler. The recognition of plasma cells and subsequently their product, a monoclonal protein has been described in detail. The authors have reviewed the treatment of multiple myeloma including the novel agents, thalidomide, bortezomib and lenalidomide.

Monoclonal immunoglobulin component (M-component) presence is suspected based on serum protein analysis using cellulose acetate membrane electrophoresis, and finally clarified by determining its immunoglobulin class using immunoelectrophoresis (IEP) or immunofixation (IFE). M-component presence is essential for diagnosing multiple myeloma (MM) and primary macroglobulinemia; however, since it is also found in non-malignant conditions, called MGUS (monoclonal gammopathy of undetermined significance), the differentiation of MGUS from malignant diseases is often important. Bence Jones protein (BJP), once detected, can support the diagnoses of MM and primary AL-amyloidosis. In the latter condition, which is often difficult to diagnose, BJP is very helpful. The newly developed method measuring free immunoglobulin light chains can effectively indicate the presence of BJP in serum. The detection of BJP in urine is still important. Capillary electrophoresis combined with immunoabsorption can detect BJP in non-concentrated urine. It may be time to take such new methods into consideration in Japan.

We report a complex and rare combination of clinical and histological findings in a 59-year-old female patient: severe sicca-syndrome due to M. Sjögren, marginal zone B-cell lymphoma (MALT-type) in labial salivary glands with localized amyloid deposition, IgM-paraproteinemia, and Bence-Jones proteinuria. The causal association of these findings could only be elucidated by intense interdisciplinary correlation of all findings.

Thiacalix[4]arenetetrasulfonate was treated with Ce(IV) in water at pH 9.5 to give novel phosphoester-hydrolyzing complexes. The dinuclear Ce(IV) complex promoted the hydrolysis of p-nitrophenyl phosphate with a turnover frequency of 6.8 h(-1) at 50 degrees C, showing fourfold higher activity than the mononuclear complex. The dinuclear complex was readily immobilized onto an antibody by simply mixing them in water, hence its phosphatase-like activity was applied to the color-developing reaction in immunoassay. The model assay using an antibody labeled with the dinuclear complex allowed the detection of as little as 10 ng mL(-1) of a tumor marker, Bence-Jones protein, in a 96-well microtiter plate format. Analysis of urine for Bence-Jones protein was performed by the proposed method.

Plasma cell dyscrasias are frequently encountered malignancies which are often associated with kidney disease through the production of monoclonal immunoglobulin (Ig). Recent advances in the field include the availability of an assay for free light chains, the introduction of new agents which more effectively target malignant plasma cells, and refinements in the application of stem-cell transplantation. Well-selected patients with plasma cell dyscrasias whose monoclonal Ig is well controlled may be candidates for kidney transplantation. Kidney transplant patients with allograft dysfunction from recurrent or de novo monoclonal Ig deposition can be successfully identified and treated with these new approaches.

Background: Detection of plasma cell dyscrasias (PCD) requires screening of serum and urine for monoclonal proteins. Several studies have demonstrated increased sensitivity and specificity when measurement of serum free light chain (SFLC) is part of the screening protocol. In addition, omission of immunofixation (IFE) in the standard work-up that includes SFLC assay has been proposed. This study attempts to define the role of the SFLC assay in a screening strategy limited to serum only. It compares outcomes to a serum-only screening strategy that omits serum IFE., Methods: Serum from 691 patients was analysed for the presence of monoclonal protein using standard serum IFE, serum protein electrophoresis (SPE) and measurement of SFLC. Data were analysed retrospectively., Results: Specificity and sensitivity of abnormal SFLC-ratios for the detection of monoclonal protein using IFE were 96% and 41%, respectively. Eighteen patients with negative monospecific and Bence Jones IFE, but abnormal SFLC-ratios were identified. In most cases, this could be attributed to kidney and inflammatory disease or haematological disorders. In four cases, this resulted in further diagnostic investigation and light chain disease was later detected in two cases. Light chain disease was confirmed in one case but not confirmed in the other patient. In 14 patients, Bence Jones IFE was negative, although the concentrations of SFLC suggested the presence of monoclonal Bence Jones protein at concentrations detectable by IFE. Thus, either the anti-serum failed at detection, there was polymerisation of the free light chains or the SFLC assay overestimated protein concentrations. Simulating a work-up that included IFE only if abnormalities were detected by SPE or the SFLC assay would have resulted in 26% fewer IFEs being performed, but three patients with monoclonal proteins by IFE would have been missed., Conclusions: Abnormal SFLC concentrations are neither sensitive nor specific for the detection of monoclonal proteins by IFE. Not all PCD are accompanied by excessive production of SFLC, and several other conditions, such as renal disease are associated with increased SFLC concentrations. An abnormal SFLC-ratio is a specific marker for PCD, and occurs primarily in patients with haematological disease. If renal and inflammatory diseases are excluded, this should prompt further diagnostic investigation. Screening of serum without performing an IFE as a standard procedure leads to a reduction of sensitivity when compared to screening of serum that includes IFE.

A Multiple Myeloma (MM) is rare in younger age group. We report MM in a 30-year-old female, who presented with multiple lytic areas upon skeletal survey, but with negative Bence Jones protein. Bone marrow biopsy confirmed it to be a case of multiple myeloma. Patient was put on chemotherapy and radiography to which she responded and now is ambulatory.

New technological evolutions have enabled new diagnostic approaches in urinalysis. Urinary flow cytometry and automated microscopic pattern recognition are two new techniques that are characterised by a much better imprecision and a higher throughput as compared to conventional microscopy of the urine sediment. Although these new techniques are well suited for the routine clinical laboratory for screening and diagnostic purposes, trained technicians are still required to verify, and if necessary, to correct the results by visual microscopy. On the other hand, automated urinary test strip analysis offers analytical, clinical, and labour cost-saving advantages. Furthermore, determination of specific urinary proteins offer interesting alternatives for diagnosis. In diabetics, the clinical significance of non-immunoreactive microalbumin needs to be established. Furthermore, the determination of specific urinary proteins alpha 1 microglobulin (as a tubular marker protein), alpha 2 macroglobulin (as a haematuria location marker) and light chains (myeloma monitoring) offer interesting diagnostic perspectives. As the information content obtained by urinalysis is complex, expert systems that make use of the various chemical and morphological parameters can offer an interesting help in the interpretation.

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.

This report by an international consensus panel updates current recommendations for defining clinical response in Waldenstrom's macroglobulinemia (WM). The previously published response criteria incorporated parameters for monoclonal protein reduction and/or improvement of marrow and nodal involvement, and included definitions of complete and partial remissions. The criteria have been updated to include minor response and stable disease categories. In addition, the criteria now recognize that delayed responses after treatment with nucleoside analogues and biologic agents and the time point for assessing response in patients with WM should be considered so as to not miss or miscategorize a response. The new criteria should therefore help in better delineating responses to therapy in patients with WM, particularly with the wide use of nucleoside analogues and biologically based agents for this disease.

Background: Positive test strip results, pathological particles in urine and the presence of proteinuria are common findings in nephropathies. A comparison between these methods and renal biopsies became available with the introduction of quantitative measurement of marker proteins (albumin, transferrin, IgG, alpha(1)-microglobulin, retinol binding protein, alpha(2)-macroglobulin, Bence Jones proteins) and standardised urine sediment analysis by flow cytometry or microscopy., Methods: A total of 400 urine samples were examined using marker protein patterns, test strips and quantitative sediment analyses., Results: Results from standardised urine sediment analyses were compared with the excretion of renal marker proteins. Increased erythrocyte and leukocyte counts in urine were observed in only 29% and 39% of the samples for which pathological protein excretion was found. The sensitivity in detecting pathological particles in urine sediment, such as casts and/or dysmorphic erythrocytes, was only 19%. Renal biopsies from 65 patients who were classified as pathological were compared with proteinuria and sediment analyses. Increased excretion of marker proteins was found in all cases, whereas only 41% of the cellular urine sediments showed pathological results., Conclusions: Quantitative measurement of marker proteins from both the glomerular and tubular sides should be used upfront as screening parameters for the early detection of renal disorders.

Immunoglobulin light chains are components of antibodies, but some exist in a free form in serum and urine as a result of their excess production over heavy chains. Free light chain (FLC) levels are of the order of milligram per liter in normal serum and urine, but marked increases have been observed in various disease conditions. It has now been established that the measurement of FLC levels contributes to diagnosis and clinical management in monoclonal gammopathies. Recent developments in FLC assays have been adapted to several automated platforms and they have now become available in laboratories. There have, however, been some concerns regarding the analytical aspects. The current assay specificity appears to be insufficient to prevent the influence of intact light chains of several orders of magnitude greater than FLCs in serum. Moreover, the heterogeneous nature of light chains makes accurate quantification unreliable. FLC assays have never been standardized because of the lack of an international reference calibrator. In this review, we summarize the reports on FLC measurements and examine the specificity of anti-FLC antibodies and the reliability of FLC assays. We also discuss difficulties in the standardization and setting of normal reference intervals for FLC assays.

Nonreducing two-dimensional gel electrophoresis (2-DE) is described for the study of immunoglobulin disorders with asynchronous production of single chains. Unlike classical reducing 2-DE, this method can distinguish between complex intact molecules and their free single chains (with different degrees of polymerization) and will thus be helpful for diagnosis of this type of disease. Examples are taken from canine patients, but the method may also be applied to both urine and serum specimens from other species. Nonreducing 2-DE thus represents a useful tool complementary to classical 2-DE, when further information about the appearance of free subunits or modifications of proteins are required, even in the presence of intact molecules.

The detection and quantification of monoclonal free light chains in urine (Bence Jones protein, BJP) are thorny issues for the laboratorian. Immunoelectrophoretic techniques (immunofixation) allow the characterization of the two pathognomonic features of light chains: monoclonality and absence of heavy chains. Immunochemical methods such as nephelometry and turbidimetry are widely used in clinical practice to exclude the presence of BJP. However, these methods are limited by several metabolic and analytical problems. The accuracy of quantitative immunochemical methods is hampered by the heterogeneous molecular forms (fragments and polymers) of BJP and by the lack of reference materials, and the precision of the methods in clinically relevant regions of the dynamic range is poorly defined. Immunoelectrophoretic methods, especially immunofixation, are recommended because of their ability to demonstrate monoclonality and the absence of heavy chains. Immunofixation is also considered the best method to document the disappearance of the monoclonal protein (complete remission). The physiology of immunoglobulins and the clinical relevance of BJP are illustrated in the two appendices to this paper.

We have developed a new method for measuring total urinary protein using acid violet 6B (AV6B) pigment. Nine purified components of human urinary proteins and urine samples collected randomly from 123 diabetic outpatients were used. There were 62, 36, and 25 cases of prenephropathy, early nephropathy, and overt nephropathy, respectively. All samples were measured by Coomassie brilliant blue G 250 (CBB), pyrogallol red-molybdate (PRM), and AV6B methods using an optical photometer. In healthy subjects, the major components of urinary proteins, such as gamma-globulins, IgG, IgA Tamm-Horsfall protein, and transferrin, the reactivity values of the AV6B and PRM methods were similar. The CBB method was the least sensitive of the three methods. In the urine samples from diabetic patients, the urinary protein values measured by the AV6B method were higher than those measured by the CBB method in the prenephropathy stage. The values obtained by the AV6B method (y) correlated well with those from the CBB method (x) (y=1.243x+3.61, r=0.904). When the values from the AV6B method (y) were compared to those from the PRM method (x), correlation was low (y=1.406x-29.15, r=0.786). In conclusion, the AV6B method was more useful than the CBB and PRM methods for low levels of urinary protein., (Copyright 2003 Wiley-Liss, Inc.)

Background: Patients with multiple myeloma often have Bence Jones proteins composed of free monoclonal light chains of the kappa or lambda type in their urine. Usually, these light chains exist as monomeric or dimeric forms, but rarely, larger molecules, such as tetramers, have been reported in the serum., Methods and Results: We report the presence of trimeric complexes of lambda light chain dimers in a patient who was diagnosed with a free lambda light chain multiple myeloma 2 years earlier and subsequently underwent a stem cell transplant. Recently, the patient presented with a large serum M-spike (23 g/L) by protein electrophoresis. The spike consisted of monoclonal lambda light chains without a heavy chain. The urine contained only 8 mg of lambda light chain in a 24-h specimen. Quantitative analysis of the serum and urinary free light chains (FLCs) indicated the probability of larger aggregates of FLCs. Size-exclusion chromatography, electrophoresis, analytical ultracentrifugation, and mass spectrometric studies of the serum revealed almost exclusively the presence of trimolecular aggregates of lambda light chain dimers without other multimeric species., Conclusion: Monoclonal lambda light chains may present as hexameric aggregates that cannot be cleared by renal excretion.

We analysed CD56 expression in 70 patients with multiple myeloma (MM) to determine its clinicopathological and prognostic significance. Fifty-five (79%) patients were CD56+. CD56- patients (n = 15) had higher beta2 microglobulin levels and a higher incidence of extramedullary disease, Bence Jones protein, renal insufficiency and thrombocytopenia than CD56+ patients. Their myelomas more frequently had a plasmablastic morphology. Overall survival was significantly lower in CD56- than CD56+ patients (22 vs 63 months, P = 0.0002). We conclude that CD56- MM is a discrete entity associated with more aggressive disease. The higher incidence of plasmablastic cases suggested that CD56- MM may develop from a less mature plasma cell than CD56+ MM.

Of the 61 newly diagnosed patients with Bence-Jones (BJ) myeloma presenting to our centre between May 1986 and December 1997, 53 received sequential therapy (ST) comprising infusional chemotherapy (IC) followed by high-dose therapy and autotransplantation with interferon-alpha2b maintenance. The outcome was compared with 153 IgG and 39 IgA similarly treated myeloma patients. Response to IC and high-dose was comparable between the three subtypes but a significantly higher proportion of patients with BJ myeloma failed to receive high-dose compared to IgG (P = 0.003) and IgA (P = 0.04) myeloma. Median overall survival (OS) of patients with BJ myeloma (2.8 years) and event-free survival (EFS, 1.2 years) was significantly shorter than for patients with IgG myeloma (4.5 years, P = 0.03 and 2.1 years, P = 0.03, respectively). However, among those patients who achieved complete remission there was no difference in OS and EFS between IgG and BJ myeloma. In distinction to IgG myeloma where age and beta2M were significant, Cox analysis on presentation features identified performance status and urine total protein as having significant impact on OS. We conclude that achieving CR is an important treatment aim in patients with BJ myeloma, conferring a similar outlook on survival as in patients with the IgG subtype, and there is a need to consider different subtype-specific staging systems when evaluating the results of published or ongoing therapeutic trials.

Monoclonal protein is the immunoglobulin and its fragments which are originated from a monoclonal clone of immunoglobulin synthesizing cell. It is an actually tumour marker for B cell lymphoproliferative disorders. It is also observed in non-lymphoproliferative disorders such as solid tumor, infection, and immunodeficiencies. Monoclonal gammopathy of undetermined significance(MGUS) can be defined as a state of pre-malignancies, especially development of myeloma should be carefully followed. The paper outlines a routine-based laboratory approach on monoclonal protein in relevance with its classification, laboratory methods and the related diseases, thus giving general orientations for the paper followed.

Localized solitary plasmacytoma of the bone (SPB) is a rare disease and is characterized by only one or two isolated bone lesions with no evidence of disease dissemination. A previously healthy 44-year-old male was admitted for evaluation of an abnormal radiographic shadow in the left middle lung field with symptoms of left back pain. Radiological evaluation revealed a peripheral opacity in the left chest wall, which was highly suspected to be a chest wall tumor. CT-guided transcutaneous needle biopsy of the tumor was performed and the specimens showed a monomorphous population of mature plasma cells. The bone marrow biopsy findings revealed no evidence of myeloma and bone scanning revealed only abnormal accumulation in the left seventh rib. He had mild M-proteins in a urine sample and Bence-Jones protein was detected. Immunoelectrophoresis revealed mild biclonal gammopathy of Bence-Jones protein of both the kappa and lambda light-chain types. Under a diagnosis of solitary bone plasmacytoma, preoperative radiation therapy with doses of 40 Gy for the tumor was performed. He underwent complete en bloc resection of the chest wall, including one-third of the left sixth and seventh ribs, the intercostal muscle and the parietal pleura. The protein abnormalities in the urine sample disappeared following surgical resection. Adjuvant chemotherapy using melphalan and prednisolone was performed. He is doing well without evidence of tumor recurrence 2 years following his initial diagnosis.

Urine protein electrophoresis (UPE) is often considered to have limited usefulness in evaluating proteinuria that is not associated with gammopathies. Unusual protein bands that are detected by UPE are commonly characterized by immunofixation electrophoresis (IFE). In this paper, electrophoretic gel patterns are shown to illustrate the greater sensitivity of IFE, compared to UPE. However, UPE remains useful for three applications: (1) UPE provides distinctive patterns that can indicate the source of proteinuria and is useful in assessing renal diseases that are independent of gammopathy; (2) combined use of UPE and IFE can avoid misinterpretations and repeated analyses of urine proteins, and (3) UPE can be used in conjunction with IFE to improve the quantitation of Bence-Jones proteinuria (BJP).

Eighteen monoclonal Bence-Jones proteins (BJPs) were examined for their effects on cultured LLC-PK1 (porcine kidney proximal tubule) cells as well as for their amidase and DNase activities. Five proteins were found to enter the cell and to gain access to the nucleus without degradation of epitopes. Intranuclear BJPs ultimately induced DNA fragmentation and cell death. BJPs with relatively high amidase activity were cytotoxic. On the other hand, three of four BJPs with DNase activity had a cytocidal effect on cultured cells; the remaining BJP, which had a relatively high DNase activity but a very low amidase activity, failed to enter the cell and was not cytotoxic in vitro. These results suggest that catalytic and cytotoxic activities of some BJPs may make a significant contribution, in a substantial proportion of myeloma patients, to the development and/or deterioration of the disease.

Background and Purpose: Solitary extramedullary plasmacytoma (EMP) represents a rare category of malignant disease on which there are limited data in regard to diagnosis, staging and natural history. This study attempted to clarify the clinical course of solitary extramedullary plasmacytoma after radiation or surgical therapy given with curative intent., Materials and Methods: The diagnosis was based on a mass of clonal plasma cells separate from bone or bone marrow without evidence of occult disease elsewhere. Between 1963 and 1996, 22 previously untreated patients with an EMP were diagnosed. Disease presented in the head or neck in 86%, usually in the nasal cavity (NC) or maxillary sinus (MS), and in these areas local bone destruction was found in 10 of 11 patients. Among all patients, serum myeloma protein was present in three patients (14%) and Bence Jones protein alone was found in two patients (9%). Radiation therapy was the sole treatment for 18 of 22 patients, and the median radiotherapy dose was 50 Gy (range, 40-60 Gy); five of seven patients with an EMP of oral cavity (OC), oropharynx (OP), nasopharynx (NP), parotid or larynx also received elective neck irradiation. Two patients underwent surgery plus postoperative irradiation of a plasmacytoma of the sigmoid colon or pleura, and two patients had resection alone of a plasmacytoma of the colon or cervical lymph node., Results: Local control was achieved in 21 of 22 patients (95%), and disease never recurred in regional nodes. Disappearance of myeloma protein occurred in three of five patients with an evaluable abnormality. Multiple myeloma developed in seven patients (32%), all within 5 years. The 5-year rate of freedom from progression to multiple myeloma was 56% and the median survival was 9.5 years., Conclusion: Radiation therapy achieved excellent locoregional control of EMP with an approximate cure fraction of 50%.

Capillary electrophoresis (CE) has been used in our teaching hospital clinical laboratory to assay approximately 13 000 specimens for serum protein electrophoresis (SPE) in 4 1/2 years. During that period we have found several unusual samples, five of which are discussed here. These samples are from separate patients with IgD myeloma, IgG heavy chain disease, a triple IgG(Kappa) monoclonal band, a rapidly changing abnormal/monoclonal band and a mixed type-11 cryoglobulinaemia. Albumin has been used to calibrate the 50-microm fused silica capillary, the quantity of the monoclonal bands being calculated by the software of either the Applied Biosystems 270A-HT or BioFocus instrument. We have found CE for the initial SPE to be a robust, labour-saving, cost effective technique, which is able to determine less than 1 g/l of monoclonal protein. However, because of the expense and time required for immunosubtraction, we prefer isoelectric focusing (IEF) for typing of paraproteins. The only samples which need care in handling are serum containing large amounts of cryoglobulin protein.

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.

A 53-year-old woman was admitted to this institution with chest pain and dyspnea. Chest roentgenogram showed pleural effusion and multiple tumor shadows, bilaterally which represented extrapleural signs. Numerous atypical plasma cells were found in the pleural effusion. Bone marrow biopsy showed atypical plasma cells. Immunoelectrophoresis revealed monoclonal Bence-Jones protein-lambda in serum and urine. Myeloma was subsequently diagnosed and chemotherapy was started. Multiple myeloma is a plasmacytoma, and myeloma cells proliferate in the bone marrow. The incidence of myeloma associated with malignant pleural effusion is rare with only 33 cases previously reported in Japan, to the best of our knowledge.

Sixty-one consecutive patients with multiple myeloma were studied with magnetic resonance (MR) imaging of the spine. Sagittal T1-weighted and short inversion time (TI) inversion recovery (STIR) images were obtained. The MR patterns of the bone marrow were classified as diffuse (D) (n=26), nodular (N) (n=11), D+N (n=13) or normal (n) (n=11). Abnormal patterns were seen in 50 (82%) of the 61 patients. Correlations were found between the MR imaging patterns and some laboratory findings (WBC, haematocrit, platelet count, serum albumin, and percentage of marrow plasmacytosis). The survival of the patients with abnormal MRI patterns was significantly poorer than that of the patients with normal patterns. However, the survival of patients with a nodular pattern did not differ from those with a normal pattern. The MR imaging pattern of the bone marrow in patients with multiple myeloma is a useful factor in the assessment of prognosis.

To improve the outcome for patients with relapsed or refractory multiple myeloma (MM), we combined idarubicin (Ida), dexamethasone and interferon (IFN) in a new regimen, 'I-Dexa'. Here we report our results of a phase I/II study using the I-Dexa protocol in an outpatient setting. A total of 31 patients were enrolled. Most patients were heavily pretreated with a median of two different chemotherapy regimen (range, 1-4). All but four patients had advanced disease (stage III). The dose of Ida was escalated to define the maximal tolerated dose (MTD) in this regimen. Four patients were treated with 5 mg/m2 and 27 patients with 7.5 mg/m2 Ida (day 1, i.v.). Dexamethasone was given at a fixed dose of 20 mg per os daily on days 2-5 and 11-14. Treatment was repeated at day 21 and consisted of up to six cycles. Patients who achieved a response or stable disease received IFN maintenance. IFN was administered three times weekly at a dose of 3 x 10(6) U/day s.c. until relapse. At the time of evaluation, 125 courses of I-Dexa were analyzed. The MTD of Ida in this regimen was 7.5 mg/m2. Hematological toxicity was mild including 5% leukocytopenia, 3% thrombocytopenia and 1% anemia (WHO grade III) at dose level 2. The MTD was defined by nonhematological toxicities including two WHO grade IV infections and one renal failure. The overall response rate including stable disease was 62.5% (PR: nine patients, 37.5%). So far, nine patients have been treated with IFN maintenance therapy with a median duration of 7 months (range, 1-16). In conclusion, I-Dexa can be given safely in an outpatient setting and is effective for the treatment of relapsed and refractory MM.

In this study, 25 multiple myeloma (MM) patients at primary diagnosis and 18 MM patients at relapse or progressive disease (PD) were examined in order to investigate the incidence of P-glycoprotein (P-gp) expression at initial diagnosis and relapse or PD. Furthermore, P-gp expression in relation to VAD regimen response was determined. P-gp expression in the myeloma cells was determined using monoclonal antibody 4E3.16 and the rhodamine 123 functional test. The percentage of patients with P-gp overexpression at primary diagnosis ranged between 0 and 41% in the literature vs 32% in our study. The percentage of P-gp positive patients at relapse or PD ranged between 29 and 59% in the literature vs 33% in this analysis. All P-gp positive patients had a functional P-gp, ie a pumping P-gp. A significant difference concerning response (50 vs 58.3%) to VAD treatment and median survival (10 vs 12.5 months) between P-gp positive and P-gp negative patients could not be determined. Six of 12 P-gp negative MM patients at relapse or PD developed after VAD therapy a relapse combined with P-gp overexpression. These results do not confirm the suggestions that P-gp overexpression influences response to VAD treatment. However, the results described in the literature and our own emphasize the need for careful accompanying research programmes aimed at detecting the complexity of chemotherapy resistance in the light of developing a risk-adapting therapy for MM patients.

The prognostic significance of of some clinical features in 41 patients with multiple myeloma (including 2 patients with plasma cell leukemia) from our institution was analyzed. Out of 14 variables isolated from the univariate analysis (P < 0.05), only three (BUN, Bence Jones protein, and chromosomal aberrations) were significant in the multivariate model (P < 0.05). Derived from these three variables, three subpopulations of patients were identified. The first group included 20 patients with a low risk of death and their median survival has not been reached. In particular, no one died during the first 60 months in this group. The second group also included 14 patients with an intermediate risk of death and a median survival of 49.2 months. The third group comprised seven patients with a high risk of death during 24 months after diagnosis and a median survival of 31.6 months (P < 0.0001). Finally, Durie & Salmon's myeloma staging system was demonstrated in the present series, and it showed prognostic validity for each stage (P < 0.0222). Compared with Durie & Salmon's staging system, our prognostic model for multiple myeloma was more useful to predict prognosis when applied to the present series.