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Oral melphalan and dexamethasone (MDex) is a standard treatment for patients with AL amyloidosis who are not eligible for stem cell transplantation at many referral centers. However, following encouraging reports on the activity of bortezomib combined with alkylators and dexamethasone, these combinations are being moved to frontline therapy. We compared the outcome of 87 patients treated with bortezomib plus MDex (BMDex) with that of 87 controls treated with MDex. Patients and controls were matched for age, cardiac and renal function and free light chain burden. A higher rate of complete responses was observed with BMDex (42 vs 19%), but this did not result in a survival improvement in the overall population. However, a significant survival advantage for BMDex was observed in patients without severe (New York Heart Association class III or IV) heart failure and with N-terminal pro-natriuretic peptide type-B <8500 ng/l. Patients treated with full-dose dexamethasone had similar response rates and survival whether they received bortezomib or not. Intermediate-risk patients who are not fit enough to receive high-dose dexamethasone are likely to take the greatest advantage from the addition of bortezomib to MDex. [ABSTRACT FROM AUTHOR]

Treatment in medical oncology is gradually shifting from the use of nonspecific chemotherapeutic agents toward an era of novel targeted therapy in which drugs and their combinations target specific aspects of the biology of tumor cells. Multiple myeloma (MM) has become one of the best examples in this regard, reflected in the identification of new pathogenic mechanisms, together with the development of novel drugs that are being explored from the preclinical setting to the early phases of clinical development. We review the biological rationale for the use of the most important new agents for treating MM and summarize their clinical activity in an increasingly busy field. First, we discuss data from already approved and active agents (including second- and third-generation proteasome inhibitors (PIs), immunomodulatory agents and alkylators). Next, we focus on agents with novel mechanisms of action, such as monoclonal antibodies (MoAbs), cell cycle-specific drugs, deacetylase inhibitors, agents acting on the unfolded protein response, signaling transduction pathway inhibitors and kinase inhibitors. Among this plethora of new agents or mechanisms, some are specially promising: anti-CD38 MoAb, such as daratumumab, are the first antibodies with clinical activity as single agents in MM. Moreover, the kinesin spindle protein inhibitor Arry-520 is effective in monotherapy as well as in combination with dexamethasone in heavily pretreated patients. Immunotherapy against MM is also being explored, and probably the most attractive example of this approach is the combination of the anti-CS1 MoAb elotuzumab with lenalidomide and dexamethasone, which has produced exciting results in the relapsed/refractory setting. [ABSTRACT FROM AUTHOR]

This manuscript summarizes the recommendations that emerged from the first Roundtable on Clinical Research in Immunoglobulin Light-chain Amyloidosis (AL), a meeting sponsored by the Amyloidosis Foundation (Clarkston, MI, USA) to develop a consensus of experts on a modern framework for clinical trial design and drug development in AL. Recent diagnostic and technical advances in AL, and updated consensus guidelines for assessing hematologic and organ responses, enable us to define study populations, appropriate end points, and other criteria for all phases of clinical research. This manuscript provides a framework for the design and conduct of systematic collaborative clinical research in AL to encourage more rapid testing of therapies and to expedite new drug development and approval. [ABSTRACT FROM AUTHOR]

Peripheral neuropathy (PN) is one of the most important complications of multiple myeloma (MM) treatment. PN can be caused by MM itself, either by the effects of the monoclonal protein or in the form of radiculopathy from direct compression, and particularly by certain therapies, including bortezomib, thalidomide, vinca alkaloids and cisplatin. Clinical evaluation has shown that up to 20% of MM patients have PN at diagnosis and as many as 75% may experience treatment-emergent PN during therapy. The incidence, symptoms, reversibility, predisposing factors and etiology of treatment-emergent PN vary among MM therapies, with PN incidence also affected by the dose, schedule and combinations of potentially neurotoxic agents. Effective management of treatment-emergent PN is critical to minimize the incidence and severity of this complication, while maintaining therapeutic efficacy. Herein, the state of knowledge regarding treatment-emergent PN in MM patients and current management practices are outlined, and recommendations regarding optimal strategies for PN management during MM treatment are provided. These strategies include early and regular monitoring with neurological evaluation, with dose modification and treatment discontinuation as indicated. Areas requiring further research include the development of MM-specific, patient-focused assessment tools, pharmacogenomic analysis of patient DNA, and trials to assess the efficacy of pharmacological interventions. [ABSTRACT FROM AUTHOR]

Monoclonal gammopathy of undetermined significance (MGUS) was identified in 3.2% of 21 463 residents of Olmsted County, Minnesota, 50 years of age or older. The risk of progression to multiple myeloma, Waldenstrom's macroglobulinemia, AL amyloidosis or a lymphoproliferative disorder is approximately 1% per year. Low-risk MGUS is characterized by having an M protein <15 g/l, IgG type and a normal free light chain (FLC) ratio. Patients should be followed with serum protein electrophoresis at six months and, if stable, can be followed every 2-3 years or when symptoms suggestive of a plasma cell malignancy arise. Patients with intermediate and high-risk MGUS should be followed in 6 months and then annually for life. The risk of smoldering (asymptomatic) multiple myeloma (SMM) progressing to multiple myeloma or a related disorder is 10% per year for the first 5 years, 3% per year for the next 5 years and 1-2% per year for the next 10 years. Testing should be done 2-3 months after the initial recognition of SMM. If the results are stable, the patient should be followed every 4-6 months for 1 year and, if stable, every 6-12 months. [ABSTRACT FROM AUTHOR]

Multiple myeloma is the most common indication for high-dose chemotherapy with autologous stem cell support (ASCT) in North America today. Stem cell procurement for ASCT has most commonly been performed with stem cell mobilization using colony-stimulating factors with or without prior chemotherapy. The target CD34+ cell dose to be collected as well as the number of apheresis performed varies throughout the country, but a minimum of 2 million CD34+ cells/kg has been traditionally used for the support of one cycle of high-dose therapy. With the advent of plerixafor (AMD3100) (a novel stem cell mobilization agent), it is pertinent to review the current status of stem cell mobilization for myeloma as well as the role of autologous stem cell transplantation in this disease. On June 1, 2008, a panel of experts was convened by the International Myeloma Foundation to address issues regarding stem cell mobilization and autologous transplantation in myeloma in the context of new therapies. The panel was asked to discuss a variety of issues regarding stem cell collection and transplantation in myeloma especially with the arrival of plerixafor. Herein, is a summary of their deliberations and conclusions. [ABSTRACT FROM AUTHOR]

The serum immunoglobulin-free light chain (FLC) assay measures levels of free κ and λ immunoglobulin light chains. There are three major indications for the FLC assay in the evaluation and management of multiple myeloma and related plasma cell disorders (PCD). In the context of screening, the serum FLC assay in combination with serum protein electrophoresis (PEL) and immunofixation yields high sensitivity, and negates the need for 24-h urine studies for diagnoses other than light chain amyloidosis (AL). Second, the baseline FLC measurement is of major prognostic value in virtually every PCD. Third, the FLC assay allows for quantitative monitoring of patients with oligosecretory PCD, including AL, oligosecretory myeloma and nearly two-thirds of patients who had previously been deemed to have non-secretory myeloma. In AL patients, serial FLC measurements outperform PEL and immunofixation. In oligosecretory myeloma patients, although not formally validated, serial FLC measurements reduce the need for frequent bone marrow biopsies. In contrast, there are no data to support using FLC assay in place of 24-h urine PEL for monitoring or for serial measurements in PCD with measurable disease by serum or urine PEL. This paper provides consensus guidelines for the use of this important assay, in the diagnosis and management of clonal PCD.Leukemia (2009) 23, 215–224; doi:10.1038/leu.2008.307; published online 20 November 2008 [ABSTRACT FROM AUTHOR]

Primary light chain-associated amyloidosis (AL) is a plasma cell dyscrasia that causes morbidity via systemic tissue deposition of monoclonal light chains in the form of fibrils (amyloid). It is the most common form of systemic amyloidosis in Western countries and is rapidly fatal. Knowledge of the pathobiology of the underlying B cell clone is of primary importance for the design and optimization of therapeutic strategies. [ABSTRACT FROM AUTHOR]

Amyloid A (SAA) and procalcitonin (PCT) have been reported as useful indicators of inflammation. Our aim was to assess the utility of SAA and PCT in establishing the severity of acute pancreatitis in comparison to C-reactive protein (CRP): Thirty-one patients with acute pancreatitis enrolled within 24 hr from the onset of pain and 31 healthy subjects were studied. Nineteen patients had mild acute pancreatitis, and 12 had severe pancreatitis. Serum SAA, PCT, and CRP were measured in all subjects at admission and, in acute pancreatitis patients, during the following five days. Patients with acute pancreatitis had serum concentrations of SAA, PCT, and CRP significantly higher (P < 0.001) than those of healthy subjects during the entire study period. Using cutoff values ranging from 240 to 250 mg/liter for SAA, from 0.252 to 0.255 ng/ml for PCT, and from 12.8 to 12.9 mg/dl for CRP, the sensitivity (calculated on patients with severe pancreatitis), the specificity (calculated on patients with mild pancreatitis), and the efficiency (calculated as the percentage of correct classifications) were 76.8%, 69.3%, and 72.4% for SAA; 21.7%, 83.2%, and 58.2% for PCT; and 60.9%, 89.1%, and 77.6% for CRP. In conclusion, the sensitivity of SAA is significantly higher than that of PCT and CRP in assessing the severity of pancreatitis, whereas PCT and CRP had a specificity significantly higher than SAA. The accuracy and efficiency were similar for SAA and CRP, and both these markers had an accuracy and efficiency significantly higher than those of PCT. [ABSTRACT FROM AUTHOR]

We have recently described an anti-β2-microglobulin (β2-m) monoclonal antibody (mAb 14H3) capable of recognizing the epitope 92–99 of the protein in the monomeric native state as well as in the fibrillar polymeric state, but not in the major histocompatibility complex type I (MHCI) anchored to the cell membrane. In the present study, we investigated the molecular basis for the inaccessibility of the C-terminal end of β2-m in the MHCI complex, and demonstrated that mAb 14H3 binds the soluble fraction of the MHCI complex with a Kd of 0.3 μM. An interaction between the complex and the membrane protects β2-m from immunological recognition at the MHCI level. This protection from antibody recognition can be weakened by procedures such as heat shock or γ irradiation that perturb the membrane structure and commit the cell to the apoptotic pathway. mAb 14H3 can recognize MHCI in a transient state that most likely precedes β2-m shedding and may be proposed as a useful tool for dynamic analysis of MHCI conformational modifications. [ABSTRACT FROM AUTHOR]

In primary systemic amyloidosis, small numbers of bone marrow plasma cells secrete monoclonal light chains that form extracellular fibrils (amyloid) in various organs. Evidence limited to a few cases suggests that rare clonal elements can also be found in the peripheral blood (PB), and this may be relevant in PB stem cell autotransplantation. Since up to 40% of amyloid clones do not synthesize heavy chains, in order to detect tumor cells with high specificity and sensitivity we developed a seminested allele-specific oligonucleotide polymerase chain reaction for tumor light chains. Clone-related sequences were detected in DNA and/or cDNA from the PB cells of eight of 10 patients at diagnosis and from apheretic collections of three of four cases undergoing PB progenitor autotransplantation. Since there are experimental data suggesting that circulating tumor cells may be involved in the growth of the amyloidogenic clone and may be chemoresistant, these findings are relevant to the use of leukapheresis purging strategies for PB progenitor autotransplantation in amyloidosis. [ABSTRACT FROM AUTHOR]

Abstract. Radiolabelled serum amyloid P component (SAP) is a specific tracer for amyloid. Iodine-123 has ideal physical characteristics for scintigraphy but is expensive and not widely available. Here we report serial imaging and turnover studies in which we labelled SAP with iodine-131, a cheap alternative isotope which would be expected to yield poorer images but permit more prolonged turnover measurements. Imaging and plasma clearance and whole body retention (WBR) of tracer were studied for up to 7 days in ten patients with proven systemic AL amyloidosis and two patients in whom the diagnosis was suspected, after i.v. administration of about 37 MBq of [sup 131]I-SAP. Normal blood pool images were obtained in the latter two subjects and amyloidosis was subsequently refuted histologically. WBR at 48 h was <60% and 6-h plasma activity was >65% of the injected dose (i.d.). Among the other ten patients, amyloid deposits were identified in the spleen in eight cases, liver in five and kidneys in four; other sites that gave positive results included bone, joints and soft tissues, and the myocardium in one case. Up to 95% of the tracer localised into amyloid within 6-h, and the values for WBR became progressively more discriminating during the study period, exceeding the normal reference value (<25%) in all cases by day 7. The optimal... [ABSTRACT FROM AUTHOR]

Fifteen patients with multiple myeloma, two of whom had plasma cell leukemia, were treated between May 1974 and December 1978. Peptichemio was administered intravenously at doses of 40-80 mg/48 h, courses including 4-17 administrations in association with moderate doses of prednisone (15-50 mg/day) and androstanes at high dosages (250 mg weekly). In two patients PTC was associated with vincristine (VCR) administered on the first day of the course. Eight patients were previously untreated, four had been resistant to melphalan (MPH) and/or cyclophosphamide (CTX), and three had been treated irregularly with one or both of these alkylating agents. The criteria of response to therapy are reported. Out of a total of 15 PTC courses administered we obtained 13 responses, eight complete and five partial; no response was achieved in the other two patients. In the four patients who were resistant to MPH and/or CTX we obtained three responses, which were maintained with the same alkylating agent to which they had been resistant previously. The time needed to obtain a response in 90% of the patients was 6 weeks. Peptichemio was shown to be effective in patients in an advanced stage of the disease, in patients with light-chain myeloma and in those with plasma cell leukemia. The association of VCR potentiated the antitumor effect, but also increased the myelotoxicity. The PTC treatment was well tolerated. It is suggested that PTC be used in induction treatment of myelomatosis and in patients resistant to traditional alkylating agents. [ABSTRACT FROM AUTHOR]

Peptichemio (PTC) is a mixture of six synthetic oligopeptides, each of which contains the alkylating residue m-[di(2-chloroethyl)amino]-L-phenylalanine (L-mSL). The fate of PTC was investigated in eight patients with multiple myeloma after intravenous infusion of the drug. The quantitative analysis of the plasma samples was performed by liquid chromatography with fluorometric detection. L-mSL was rapidly released from the peptides and reached its maximal plasma concentration at the end of the infusion. Its median elimination half-life was 1.73 (range, 0.72-2.41) h. It was possible to follow the concentration of only one of the peptides, L-mSL-L-Arg(NO2)-L-Nval.OEt, during and shortly after the infusion of PTC. The stability of L-mSL and the peptides was studied in buffer solution (pH 7.3), plasma, and blood. The stability of some of the peptides was drastically decreased in blood, the degradation half-lives being only about 1 min. We conclude that L-mSL plays an important role in the mechanism of action of PTC. [ABSTRACT FROM AUTHOR]