Bortezomib-based triplets are associated with a high probability of dialysis independence and rapid renal recovery in newly diagnosed myeloma patients with severe renal failure or those requiring dialysis

Renal failure (RF) is a common and severe complication of symptomatic myeloma, associated with significant morbidity and mortality. Such patients are commonly excluded from clinical trials. Bortezomib/dexamethasone (VD)-based regimens are the backbone of the treatment of newly diagnosed MM patients who present with severe RF even those requiring dialysis. We analyzed the outcomes of 83 consecutive bortezomib-treated patients with severe RF (eGFR < 30 ml/min/1.73 m(2) ), of which 31 (37%) required dialysis. By IMWG renal response criteria, 54 (65%) patients achieved at least MRrenal, including CRrenal in 35% and PRrenal in 12%. Triplet combinations (i.e., VD plus a third agent) versus VD alone were associated with higher rates of renal responses (72 vs. 50%; P = 0.06). Fifteen of the 31 (48%) patients became dialysis independent within a median of 217 days (range 11-724). Triplets were associated with a higher probability of dialysis discontinuation (57 vs. 35%). Serum free light chain (sFLC) level ≥11,550 mg/L was associated with lower rates of major renal response, longer time to major renal response, lower probability, and longer time to dialysis discontinuation. Rapid myeloma response (≥PR within the first month) was also associated with higher rates of renal response. Patients who became dialysis-independent had longer survival than those remaining on dialysis. In conclusion, VD-based triplets are associated with a significant probability of renal response and dialysis discontinuation, improving the survival of patients who became dialysis independent. Rapid disease response is important for renal recovery and sFLCs are predictive of the probability and of the time required for renal response.

International Myeloma Working Group Recommendations for the Diagnosis and Management of Myeloma-Related Renal Impairment

Purpose

The aim of the International Myeloma Working Group was to develop practical recommendations for the diagnosis and management of multiple myeloma–related renal impairment (RI).

Methods

Recommendations were based on published data through December 2015, and were developed using the system developed by the Grading of Recommendation, Assessment, Development, and Evaluation Working Group.

Recommendations

All patients with myeloma at diagnosis and at disease assessment should have serum creatinine, estimated glomerular filtration rate, and electrolytes measurements as well as free light chain, if available, and urine electrophoresis of a sample from a 24-hour urine collection (grade A). The Chronic Kidney Disease Epidemiology Collaboration, preferably, or the Modification of Diet in Renal Disease formula should be used for the evaluation of estimated glomerular filtration rate in patients with stabilized serum creatinine (grade A). International Myeloma Working Group criteria for renal reversibility should be used (grade B). For the management of RI in patients with multiple myeloma, high fluid intake is indicated along with antimyeloma therapy (grade B). The use of high-cutoff hemodialysis membranes in combination with antimyeloma therapy can be considered (grade B). Bortezomib-based regimens remain the cornerstone of the management of myeloma-related RI (grade A). High-dose dexamethasone should be administered at least for the first month of therapy (grade B). Thalidomide is effective in patients with myeloma with RI, and no dose modifications are needed (grade B). Lenalidomide is effective and safe, mainly in patients with mild to moderate RI (grade B); for patients with severe RI or on dialysis, lenalidomide should be given with close monitoring for hematologic toxicity (grade B) with dose reduction as needed. High-dose therapy with autologous stem cell transplantation (with melphalan 100 mg/m2 to 140 mg/m2) is feasible in patients with RI (grade C). Carfilzomib can be safely administered to patients with creatinine clearance > 15 mL/min, whereas ixazomib in combination with lenalidomide and dexamethasone can be safely administered to patients with creatinine clearance > 30 mL/min (grade A).

Lenalidomide is effective and safe for the treatment of patients with relapsed multiple myeloma and very severe renal impairment

Patients with multiple myeloma (MM) and severe renal impairment (SRI) have shorter survival than MM patients without renal failure. Although lenalidomide is a highly active drug, this immunomodulatory agent is frequently neglected in this context due to its predominant renal clearance and, consequently, an increased risk of toxicity. This risk might be overcome with the proper lenalidomide dose adjustment to renal function. This study evaluates the outcomes of 23 relapsed MM patients with SRI (baseline creatinine clearance (CrCl) <30 mL/min) treated with lenalidomide-dexamethasone (LenDex), including 56 % (13 patients) under hemodialysis. The median CrCl at start of LenDex was 19 mL/min; an overall response rate (partial response or better) of 56 % was obtained, with a median follow-up from start of LenDex of 52 months (8-79). The median time until maximal response was 4 months, and in 58 % (7/12), the response was longer than 2 years. Nine percent had renal improvement, but all the 13 patients on hemodialysis remained under treatment. LenDex was interrupted in three cases because of adverse events (infections and cutaneous events); 78 % of the patients were on thromboprophylaxis with aspirin. It is important to notice that, after initial dose adjustment of therapy, there should be a continuous process of dose adjustment, taking into account variations in renal function. Furthermore, lenalidomide dose adjustment should be made according to the individual tolerance, even with stable renal function. LenDex dose adjustment, according to these principles, does not negatively impact response and improves treatment tolerance. It has a clear potential to treat this group of patients and to induce long duration of responses [event-free survival (EFS) 20.5 m and overall survival (OS) 42.6 m].

Serum free light chain assays not total light chain assays are the standard of care to assess Monoclonal Gammopathies

The diagnosis of Multiple Myeloma is a challenge to the physician due to the non-specific symptoms (anemia, bone pain and recurrent infections) that are commonplace in the elderly population. However, early diagnosis is associated with less severe disease, including fewer patients presenting with acute renal injury, pathological fractures and severe anemia. Since 2006, the serum free light chain test Freelite(®) has been included alongside standard laboratory tests (serum and urine protein electrophoresis, and serum and urine immunofixation) as an aid in the identification of monoclonal proteins, which are a cornerstone for the diagnosis of Multiple Myeloma. The serum free light chain assay recognizes the light chain component of the immunoglobulin in its free form with high sensitivity. Other assays that measure light chains in the free and intact immunoglobulin forms are sensitive, but unfortunately, due to the nomenclature used, these assays (total light chains) are sometimes used in place of the free light chain assay. This paper reviews the available literature comparing the two assays and tries to clarify hypothetical limitations of the total assay to detect Multiple Myeloma. Furthermore, we elaborate on our study comparing the two assays used in 11 Light Chain Multiple Myeloma patients at presentation and 103 patients taken through the course of their disease. The aim of this article is to provide a clear discrimination between the two assays and to provide information to physicians and laboratory technicians so that they can utilize the International Myeloma Working Group guidelines.

Current Trends of Renal Impairment in Multiple Myeloma

BACKGROUND

Renal impairment (RI) is a common complication of multiple myeloma (MM). Around 50% of patients with MM have RI at presentation, and up to 5% require dialysis treatment. Severe acute kidney injury (AKI) as a cause of RI is a particular challenge as historically the survival of patients who sustain this complication and require dialysis is very poor. However, in this current period, survival is improving and the focus is on optimum use of novel chemotherapies and the evaluation of extra-corporeal therapies for removal of serum immunoglobulin light chains.

SUMMARY

RI in patients with MM is commonly associated with excess monoclonal free light chain (FLC) production; myeloma cast nephropathy is the predominant renal pathology in patients presenting with severe RI secondary to AKI. The majority of patients have mild to moderate RI and recover renal function. However, patients with more severe RI, in particular those with a requirement for dialysis, are less likely to recover renal function. Rapid diagnosis and prompt institution of anti-myeloma therapy is an important determinant of renal function recovery, through targeting early and sustained reduction of involved monoclonal FLC. Novel agents are associated with excellent disease response, and bortezomib is now widely used as a first-line agent in the management of MM in patients with severe RI. Extended haemodialysis using high cut-off dialysers is more effective for extracorporeal removal of FLC than plasma exchange, and clinical trials are in process. High-dose chemotherapy with autologous stem cell transplantation does have a role in patients with severe RI but requires careful patient selection.

KEY MESSAGES

RI is very common in patients with MM, and renal function recovery is associated with improved clinical outcomes. We summarise the epidemiology of MM in the UK, present the impact of RI and renal function recovery on patient outcome, and describe the current management of MM in western countries.

FACTS FROM EAST AND WEST

(1) A serum creatinine level >2 mg/dl has been reported in 16, 21, 24, and 33% of patients with MM in cohort studies from Japan, Europe, China, and Korea, respectively. A creatinine clearance rate <30 ml/min was observed in 30 and 15% of patients in Chinese and Western MM cohorts, respectively. The commonest cause of severe RI in patients with MM is myeloma cast nephropathy. (2) The efficacy of novel treatments (bortezomib, carfilzomib, thalidomide, and lenalidomide) has predominantly been assessed in Western patients. Bortezomib and dexamethasone are the current standard of care for MM and severe RI in the West. Severe RI is not a contraindication to autologous stem cell transplantation (ASCT). Most of the data are from the West; there are case reports from China describing good outcomes with ASCT. The removal of FLC by high-cut-off hemodialysis is under evaluation in randomized controlled trials (RCTs) in the West. Studies in this area are not yet conducted in China. In China, new treatments, such as bortezomib, are more widely used than before, and favorable results are being reported; however, RCT studies are still needed in this area to confirm the efficacy and safety of this and other novel treatments.

The Prevalence and Management of Multiple Myeloma-Induced Kidney Disease in China

BACKGROUND

Multiple myeloma (MM) is a clonal B-cell malignancy of the bone marrow. Renal impairment is a common complication of MM. So far, there is no systematic overview of MM-induced kidney disease in China.

SUMMARY

The incidence of MM is 0.6/100,000 in China. Twenty-four, 19.7, and 30.8% of all patients with MM had renal insufficiency [defined by serum creatinine (Scr) ≥2 mg/dl] at diagnosis in China mainland, Hong Kong and Taiwan, respectively. Novel criteria based on the estimated glomerular filtration rate measurements are recommended for the assessment of renal function in patients with MM with stabilized Scr. It is reported that 78% of the MM patients had a creatinine clearance rate (Ccr) <90 ml/min, and 30.5% had a Ccr <30 ml/min. The IgG type was the most prevalent in MM patients; the light-chain and IgD type usually had a higher rate of kidney damage than others. New more effective drugs, blood purification technology and peripheral blood autologous stem cell transplantation have been introduced in clinical practice. Unfortunately, the studies conducted in the patients with renal insufficiency were almost all retrospective, had a small sample size and a short follow-up time. Although new treatments such as bortezomib are more widely used than before, traditional chemotherapy is still used, also because of economic constraints. The RIFLE criteria, which seem to be appropriate to define the severity of acute kidney injury (AKI), have been extensively validated worldwide but rarely in patients with MM. It was the first time to apply the RIFLE system to analyze the natural history of MM patients with AKI retrospectively in our unit. The severity of AKI defined by using the RIFLE criteria (OR = 2.04, p = 0.06) was associated with a marginal better long-term outcome.

KEY MESSAGES

Novel criteria of renal insufficiency should be introduced into practice when treating MM. The treatment of MM patients with kidney disease has been greatly improved recently. It is necessary to conduct further large randomized controlled trials of the long-term outcome in China.

FACTS FROM EAST AND WEST

(1) An Scr level >2 mg/dl has been reported in 16, 21, 24, and 33% of patients with MM in cohort studies of Japan, Europe, China, and Korea, respectively. A Ccr <30 ml/min was observed in 30 and 15% of patients in Chinese and Western MM cohorts, respectively. The commonest cause of severe renal impairment (RI) in patients with MM is myeloma cast nephropathy. (2) The efficacy of novel treatments (bortezomib, carfilzomib, thalidomide, and lenalidomide) has predominantly been assessed in Western patients. Bortezomib and dexamethasone are the current standard of care for MM and severe RI in the West. Severe RI is not a contraindication to autologous stem cell transplantation (ASCT). Most of the data are from the West; there are case reports from China describing good outcomes with ASCT. The removal of free light chain by high cutoff hemodialysis is under evaluation in randomized controlled trials (RCTs) in the West. Studies in this area are not yet conducted in China. In China, new treatments, such as bortezomib, are more widely used than before and favorable results are being reported; however, RCT studies are still needed in this area to confirm the efficacy and safety of this and other novel treatments.

Trends in Survival and Renal Recovery in Patients with Multiple Myeloma or Light-Chain Amyloidosis on Chronic Dialysis

BACKGROUND AND OBJECTIVES

Monoclonal gammopathies (MGs) with renal involvement can lead to ESRD caused by myeloma cast nephropathy (MCN), immunoglobulin light chain amyloidosis (ALA), or light-chain deposition disease (LCDD). Few studies have focused on the prognosis of patients with MG on chronic dialysis. We evaluated the outcomes of patients with MG incident on chronic dialysis in France.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

All incident patients registered in the Renal Epidemiology and Information Network Registry between 2002 and 2011 with ESRD caused by ALA, LCDD, or MCN were included. Patient's survival, censored for renal transplantation, renal recovery, and loss to follow-up, as well as renal outcomes were analyzed and compared with a control group. Risk factors and causes of death were analyzed.

RESULTS

We included 1459 patients, comprising 265 (18%) patients with ALA, 334 (23%) patients with LCDD, and 861 (59%) patients with MCN. Median age was 72 years, and 56% were men. Median follow-up was 13.1 months. Renal recovery was observed in 9.1% of patients and more frequent after 2006. Kidney transplantation was rare in this population (2.3%). Among 1272 patients who remained on dialysis, 67% died. Median survival on dialysis was 18.3 months. Main causes of death were malignancies (34.4%), cardiovascular diseases (18%), infections (13.3%), and cachexia (5.2%). Independent risk factors of death were age (hazard ratio [HR], 1.03 per year increase; 95% confidence interval [95% CI], 1.02 to 1.03), frailty (HR, 1.93; 95% CI, 1.58 to 2.36), congestive heart failure (HR, 1.54; 95% CI, 1.23 to 1.93), and dialysis initiation on a central catheter (HR, 1.40; 95% CI, 1.11 to 1.75). Factors associated with a lower risk of death were year of dialysis initiation (HR, 0.95 per year increase; 95% CI, 0.91 to 0.99) and high BP (HR, 0.80; 95% CI, 0.67 to 0.97).

CONCLUSIONS

Survival of patients with ALA, LCDD, or MCN on chronic dialysis is poor but has improved over time. Progressive malignancy is the main cause of death in this population. Renal recovery has increased since 2006.

Effectiveness of Haemodiafiltration with Heat Sterilized High-Flux Polyphenylene HF Dialyzer in Reducing Free Light Chains in Patients with Myeloma Cast Nephropathy

INTRODUCTION

In cases of myeloma cast nephropathy in need of haemodialysis (HD), reduction of free light chains using HD with High-Cut-Off filters (HCO-HD), in combination with chemotherapy, may be associated with better renal recovery. The aim of the present study is to evaluate the effectiveness of haemodiafiltration (HDF) in reducing free light chain levels using a less expensive heat sterilized high-flux polyphenylene HF dialyzer (HF-HDF).

METHODS

In a single-centre prospective cohort study, 327 dialysis sessions were performed using a 2.2 m2 heat sterilized high-flux polyphenylene HF dialyzer (Phylther HF22SD), a small (1.1m2) or large (2.1 m2) high-cut-off (HCO) dialyzer (HCOS and HCOL) in a cohort of 16 patients presenting with dialysis-dependent acute cast nephropathy and elevated free light chains (10 kappa, 6 lambda). The outcomes of the study were the mean reduction ratio (RR) of kappa and lambda, the proportion of treatments with an RR of at least 0.65, albumin loss and the description of patient outcomes. Statistical analysis was performed using linear and logistic regression through generalized estimating equation analysis so as to take into account repeated observation within subjects and adjust for session duration.

RESULTS

There were no significant differences in the estimated marginal mean of kappa RR, which were respectively 0.67, 0.69 and 0.70 with HCOL-HD, HCOS-HDF and HF-HDF (P = 0.950). The estimated marginal mean of the proportions of treatments with a kappa RR ≥0.65 were 68%, 63% and 71% with HCOL-HD, HCOS-HDF and HF-HDF, respectively (P = 0.913). The estimated marginal mean of lambda RR were higher with HCOL-HDF (0.78), compared to HCOL-HD and HF-HDF (0.62, and 0.61 respectively). The estimated marginal mean proportion of treatments with a lambda RR ≥0.65 were higher with HCOL-HDF (81%), compared to 57% in HF-HDF (P = 0.042). The median albumin loss were 7, 21 and 63 g/session with HF-HDF, HCOL-HD and HCOL-HDF respectively (P = 0.044). Among survivors, 9 out of 10 episodes of acute kidney injuries became dialysis-independent following a median time of renal replacement therapy of 40 days (range 7-181).

CONCLUSION

Therefore, in patients with acute dialysis-dependent myeloma cast nephropathy, in addition to chemotherapy, HDF with a heat sterilized high-flux polyphenylene HF dialyzer could offer an alternative to HCO dialysis for extracorporeal kappa reduction with lower albumin loss.

Plasmapheresis in cast nephropathy: yes or no?

PURPOSE OF REVIEW

Renal failure is a frequent complication of multiple myeloma and portends a poor prognosis. Plasmapheresis has been suggested as an adjunct to chemotherapy to halt or reverse renal injury associated with multiple myeloma. The purpose of this article is to review the rationale for using plasmapheresis for this indication and then provide a discussion of the evidence regarding its use.

RECENT FINDINGS

The outcome of patients with multiple myeloma has improved considerably in recent years, mostly owing to the introduction of new highly effective chemotherapeutic agents. However, patients with renal failure who do not recover independent renal function continue to have very poor prognosis. Recent evidence now indicates that an early and sustained reduction in circulating free light chains (FLCs) is associated with improved renal recovery in patients with myeloma kidney. Extracorporeal removal of FLCs with plasmapheresis, or other techniques, can achieve rapid and sustained reduction in serum FLC concentration in patients with acute myeloma kidney. Unfortunately, there is currently no convincing evidence in the literature that the addition of mechanical removal of FLC to standard chemotherapy translates into clinical benefits for patients.

SUMMARY

Plasmapheresis is theoretically attractive as a means of rapidly lowering serum FLC burden in the hope of reducing nephrotoxicity in patients with multiple myeloma. However, the role of plasmapheresis in improving renal prognosis and patient survival remains to be demonstrated.

Patients with multiple myeloma have excellent long-term outcomes after recovery from dialysis-dependent acute kidney injury

OBJECTIVES

The aim of this study was to report the long-term outcomes in patients with multiple myeloma (MM) who receive dialysis treatment for acute kidney injury (AKI) due to myeloma cast nephropathy and subsequently recover renal function.

METHODS

Patients presenting with dialysis-dependent AKI secondary to myeloma cast nephropathy and subsequently recovering independent renal function between January 2005 and December 2012 were included in this study. Both renal and haematological parameters were collected at multiple time points as part of routine clinic practice. Factors associated with renal function and overall survival (OS) were determined.

RESULTS

Twenty-four patients fulfilled the criteria for inclusion. Mean age was 62.1 years; 75% were male and 75% were of White ethnicity. The median OS was 64.1 months (95% confidence interval [CI] 34.8-93.3). Twenty-three (95.8%) patients remained dialysis-independent until death or end of follow-up; one patient required further haemodialysis treatment during the follow-up period. The independent determinant of worse OS was a known history of chronic kidney disease (CKD) at presentation. Shorter length of time on haemodialysis and higher percentage reduction in clonal serum FLC at day 21 from baseline predicted better excretory renal function (estimated glomerular filtration rate) at 6 months.

CONCLUSION

In this series, the large majority of patients with MM and dialysis-dependent AKI secondary to myeloma cast nephropathy who recovered independent renal function had no requirement for further dialysis. Survival following recovery of renal function is good, and early variables are independently associated with survival and future renal function.

The changing trends and outcomes in renal replacement therapy: data from the ERA-EDTA Registry

BACKGROUND

This study examines the time trends in incidence, prevalence, patient and kidney allograft survival and causes of death (COD) in patients receiving renal replacement therapy (RRT) in Europe.

METHODS

Eighteen national or regional renal registries providing data to the European Renal Association-European Dialysis and Transplant Association Registry between 1998 and 2011 were included. Incidence and prevalence time trends between 2001 and 2011 were studied with Joinpoint and Poisson regression. Patient and kidney allograft survival and COD between 1998 and 2011 were analysed using Kaplan-Meier and competing risk methods and Cox regression.

RESULTS

From 2001 to 2008, the adjusted incidence of RRT rose by 1.1% (95% CI: 0.6, 1.7) annually to 131 per million population (pmp). During 2008-2011, the adjusted incidence fell by 2.2% (95% CI: -4.2, -0.2) annually to 125 pmp. This decline occurred predominantly in patients aged 45-64 years, 65-74 years and in the primary renal diseases diabetes mellitus type 1 and 2, renovascular disease and glomerulonephritis. Between 2001 and 2011, the overall adjusted prevalence increased from 724 to 1032 pmp (+3.3% annually, 95% CI: 2.8, 3.8). The adjusted 5-year patient survival on RRT improved between 1998-2002 and 2003-2007 [adjusted hazard ratio (HRa) 0.85, 95% CI: 0.84, 0.86]. Comparing these time periods, the risk of cardiovascular deaths fell by 25% (HRa 0.75, 95% CI: 0.74, 0.77). However the risk of malignant death rose by 9% (HRa 1.09, 95% CI: 1.03, 1.16) in patients ≥65 years.

CONCLUSION

This European study shows a declining RRT incidence, particularly in patients aged 45-64 years, 65-74 years and secondary to diabetic nephropathy. Encouragingly, the adjusted RRT patient survival continues to improve. The risk of cardiovascular death has decreased, though the risk of death from malignancy has increased in the older population.

New aspects on the pathogenesis of renal disorders related to monoclonal gammopathies

BACKGROUND

Multiple myeloma and other related monoclonal gammopathies are frequently encountered conditions associated with renal damage, especially in elderly population. They are arising from clonal proliferation of plasma cells in bone marrow producing various quantities of abnormal monoclonal immunoglobulins, or their components/fragments.

SUMMARY

These abnormal proteins differ from normal immunoglobulins in the amino acid sequence and in the three-dimensional structure of the molecule, which may determine their toxicity. Kidney seems to be a target organ as a major catabolic site. The pathology of renal disease is highly heterogeneous involving a variety of different mechanisms, which are divided into immunoglobulin dependent and immunoglobulin independent mechanisms. The Ig-dependent mechanisms may involve the four components of the kidney parenchyma, and the primary structure of these proteins determine the pattern of renal disease.

KEY MESSAGE

This review summarizes the existing literature in the pathobiology of multiple myeloma, and the pathological properties of the M-proteins, focusing on the mechanisms of the renal manifestations related to these abnormal proteins, especially glomerular injury. Also it supports the opinion that monoclonal gammopathy of undetermined significance (MGUS) should not be used in cases where there is proven renal impairment due to these proteins, even if it is mild and does not meet the current criteria.

Severe acute kidney injury and multiple myeloma: evaluation of kidney and patient prognostic factors

BACKGROUND

Patients with multiple myeloma (MM) manifesting acute kidney injury (AKI) and who later recover renal function and independence from renal replacement therapy (RRT) are considered to have a better outcome. The aim of this work was to study the factors associated with renal function recovery (independence of hemodialysis) and longer survival in these patients.

METHODS

A retrospective single center study including patients with a diagnosis of MM and severe AKI, defined as stage 3 of the Kidney Disease: Improving Global Outcomes (KDIGO) criteria: 3.0 times baseline increase in serum creatinine (sCr) or increase in sCr to ≥4.0mg/dL or initiation of RRT, was conducted. Data was registry-based and collected between January 2000 and December 2011. We examined demographic and laboratorial data, presenting clinical features, precipitating factors, need for RRT and chemotherapy. Death was considered the primary endpoint.

RESULTS

Lower serum β2-microglobulin was the only independent factor associated with recovery of renal function and independence of RRT (OR 0.95, 95% CI: 0.91-0.99, P=0.02). The median survival after AKI was 10.7±12.1months. The factors associated with longer survival were independence of RRT (HR 2.21; 95% CI: 1.08-4.49; P=0.02), lower CRP (HR 1.07; 95% CI: 1.03-1.12; P=0.001) and younger age (HR 1.03; 95% CI: 1.01-1.06; P=0.005).

CONCLUSIONS

Our study suggests that MM patients with lower serum β2-microglobulin have a higher likelihood of recovering renal function after severe AKI. Independence of RRT, lower CRP and younger age are associated with longer survival.

Pathogenesis of renal failure in multiple myeloma: any role of contrast media?

The spectrum of kidney disease-associated monoclonal immunoglobulin and plasma cell malignancies is remarkably broad and encompasses nearly all nephropathologic entities. Multiple myeloma with kidney impairment at presentation is a medical emergency since the recovery of kidney function is associated with survival benefits. In most cases, kidney impairment may be the first clinical manifestation of malignant plasma cell dyscrasias like multiple myeloma and light chain amyloidosis. Multiple myeloma per se cannot be considered a main risk factor for developing acute kidney injury following intravascular administration of iodinated contrast media. The risk is increased by comorbidities such as chronic kidney disease, diabetes, hypercalcemia, dehydration, and use of nephrotoxic drugs. Before the administration of contrast media, the current recommended laboratory tests for assessing kidney function are serum creatinine measurement and the estimation of glomerular filtration rate by using the CKD-EPI equation. The assessment of Bence Jones proteinuria is unnecessary for evaluating the risk of kidney failure in patients with multiple myeloma, since this test cannot be considered a surrogate biomarker of kidney function.

Multiple myeloma and kidney disease

Multiple myeloma (MM) has a high incidence rate in the elderly. Responsiveness to treatments differs considerably among patients because of high heterogeneity of MM. Chronic kidney disease (CKD) is a common clinical feature in MM patients, and treatment-related mortality and morbidity are higher in MM patients with CKD than in patients with normal renal function. Recent advances in diagnostic tests, chemotherapy agents, and dialysis techniques are providing clinicians with novel approaches for the management of MM patients with CKD. Once reversible factors, such as hypercalcemia, have been corrected, the most common cause of severe acute kidney injury (AKI) in MM patients is tubulointerstitial nephropathy, which results from very high circulating concentrations of monoclonal immunoglobulin free light chains (FLC). In the setting of AKI, an early reduction of serum FLC concentration is related to kidney function recovery. The combination of extended high cutoff hemodialysis and chemotherapy results in sustained reductions in serum FLC concentration in the majority of patients and a high rate of independence from dialysis.

Acute kidney injury and bisphosphonate use in cancer: a report from the research on adverse drug events and reports (RADAR) project

PURPOSE

To determine whether acute kidney injury (AKI) is identified within the US Food and Drug Administration's Adverse Events and Reporting System (FDA AERS) as an adverse event resulting from bisphosphonate (BP) use in cancer therapy.

METHODS

A search of the FDA AERS records from January 1998 through June 2009 was performed; search terms were "renal problems" and all drug names for BPs. The search resulted in 2,091 reports. We analyzed for signals of disproportional association by calculating the proportional reporting ratio for zoledronic acid (ZOL) and pamidronate. Literature review of BP-associated renal injury within the cancer setting was conducted.

RESULTS

Four hundred eighty cases of BP-associated acute kidney injury (AKI) were identified in patients with cancer. Two hundred ninety-eight patients (56%) were female; mean age was 66 ± 10 years. Multiple myeloma (n = 220, 46%), breast cancer (n = 98, 20%), and prostate cancer (n = 24, 5%) were identified. Agents included ZOL (n = 411, 87.5%), pamidronate (n = 8, 17%), and alendronate (n = 36, 2%). Outcomes included hospitalization (n = 304, 63.3%) and death (n = 68, 14%). The proportional reporting ratio for ZOL was 1.22 (95% CI, 1.13 to 1.32) and for pamidronate was 1.55 (95% CI, 1.25 to 1.65), reflecting a nonsignificant safety signal for both drugs.

CONCLUSION

AKI was identified in BP cancer clinical trials, although a safety signal for BPs and AKI within the FDA AERS was not detected. Our findings may be attributed, in part, to clinicians who believe that AKI occurs infrequently; ascribe the AKI to underlying premorbid disease, therapy, or cancer progression; or consider that AKI is a known adverse drug reaction of BPs and thus under-report AKI to the AERS.

New primary renal diagnosis codes for the ERA-EDTA

The European Renal Association-European Dialysis and Transplant Association (ERA-EDTA) Registry has produced a new set of primary renal diagnosis (PRD) codes that are intended for use by affiliated registries. It is designed specifically for use in renal centres and registries but is aligned with international coding standards supported by the WHO (International Classification of Diseases) and the International Health Terminology Standards Development Organization (SNOMED Clinical Terms). It is available as supplementary material to this paper and free on the internet for non-commercial, clinical, quality improvement and research use, and by agreement with the ERA-EDTA Registry for use by commercial organizations. Conversion between the old and the new PRD codes is possible. The new codes are very flexible and will be actively managed to keep them up-to-date and to ensure that renal medicine can remain at the forefront of the electronic revolution in medicine, epidemiology research and the use of decision support systems to improve the care of patients.

Optimizing treatment strategies in myeloma cast nephropathy: rationale for a randomized prospective trial

Renal failure is a frequent complication of multiple myeloma (MM) that strongly affects patient survival. Although a variety of renal diseases may be observed in MM, myeloma cast nephropathy (MCN), a tubulo-interstitial disorder related to precipitation of a monoclonal light chain (LC) within tubular distal lumens, is the main cause of severe and persistent renal failure. To date, the respective frequency and initial evolution of renal disorders associated with monoclonal LC in MM remain poorly defined. Treatment of MCN relies on urgent symptomatic measures and rapid introduction of chemotherapy to reduce the production of monoclonal LC. The introduction of novel chemotherapy regimens based on the association of bortezomib with dexamethasone is likely to have improved the prognosis of MM patients with renal failure. In addition, the combination of novel agents with efficient removal of circulating LC through high cut-off hemodialysis membrane may further increase renal response rate. However, the impact on patient and renal outcomes of these potential therapeutic advances has not been evaluated in prospective studies. The randomized trials EuLITE in the UK and Germany and MYRE in France should help to answer these issues. MYRE is a randomized controlled phase III trial (NCT01208818) that aims to better define the epidemiology and typology of inaugural renal failure in MM and to optimize therapy of MCN patients with and without dialysis-dependent renal failure.

The rationale and evidence base for the direct removal of serum-free light chains in the management of myeloma kidney

Myeloma kidney (cast nephropathy) causing severe acute kidney injury occurs in up to 10% of patients with multiple myeloma. The lesion is caused by exposure of the kidneys to high serum levels of free clonal immunoglobulin light chains (LCs) and is associated with very high morbidity and mortality. The current focus on the management of this complication is on early and aggressive treatment to rapidly reduce the serum levels of the immunoglobulin LC clone and protect the kidneys from continuing injury. This has promoted intense interest in the role of direct (extracorporeal) removal of free LCs from serum by plasma exchange or high cut-off (protein permeable) hemodialysis. However, it remains uncertain whether direct removal provides an additional measurable clinical benefit over the current standard of care; rapid institution of treatment with a dexamethasone- and bortezomib-based chemotherapy regime. In this article, we review the rationale for direct removal of free LCs and the current clinical evidence base for plasma exchange and high cut-off hemodialysis.

Achieving an early myeloma response in patients with kidney impairment

There is increasing evidence, particularly in severe acute kidney injury, that treatment of multiple myeloma with regimens that include dexamethasone in combination with novel chemotherapy agents are associated with an early disease response in most patients. However, the evidence to guide the optimal chemotherapy regimen in patients with kidney impairment is limited, and treatment choices are complicated by the effect of kidney function on drug dosing. Here, we summarize the current status of this field, with a particular focus on chemotherapy regimens that are based on dexamethasone and novel agents and an outline of those areas in which further work is needed to improve the evidence base.

Myeloma kidney: improving clinical outcomes?

Renal impairment is a common complication of multiple myeloma, affecting 20% to 40% of new cases (depending on the definition). Most cases are mild and easily reversible, but it may manifest as severe acute renal injury requiring dialysis. Renal impairment is associated with a large tumor mass and consequently confers a poor prognosis. The prognosis of myeloma has improved with the introduction of novel agents and autologous stem cell transplantation. These improvements appear to apply equally to patients with renal impairment, although the risk of complication is usually higher in this group of patients. In addition to improved overall survival, there is some evidence that novel therapies have improved the renal prognosis. Treatment with high-dose dexamethasone and bortezomib can rapidly reduce light chain production and provide an opportunity for renal recovery. Although trials of plasma exchange (to remove the nephrotoxic light chain) have shown a disappointing lack of benefit, high cutoff dialysis removes larger quantities of light chain; therefore, trials are underway to investigate whether this can improve the renal prognosis independently of chemotherapy. Outcomes in patients with myeloma kidney do appear to be improving, but more trials are needed (some of which are in progress). There is cause for optimism for physicians and for patients suffering from this condition.

Impact of free light chain hemodialysis in myeloma cast nephropathy: a case-control study

New very high permeability dialysis membranes have been developed to enable the clearance of free light chains in myeloma cast nephropathy. These new dialysis techniques, in combination with chemotherapy, should allow improved prognosis in patients with myeloma cast nephropathy. We report a prospective observational study comparing patients who underwent hemodialysis in our center in 2009 for cast nephropathy revealing multiple myeloma vs. patients treated for the same condition during the same period in other centers in our region. The main difference in the management protocols was the use of high cutoff (HCO) membranes in our center. We described the clinical features, the management protocols, and the outcomes as of June 1, 2010. In 2009, five patients were treated for myeloma cast nephropathy with HCO hemodialysis in our center. At 386 ± 100 days follow-up, one patient died, while three of the five patients recovered their renal function, allowing cessation of hemodialysis. During the same period, five patients were treated for myeloma cast nephropathy in other centers in our region. At 398 ± 131 days follow-up, four patients died, and none of the patients recovered renal function, allowing cessation of hemodialysis. In our study, light chain clearance allowed recovery of renal function and cessation of hemodialysis in three of five patients with acute kidney injury secondary to myeloma cast nephropathy. A randomized trial comparing this technique with conventional hemodialysis techniques should be conducted to raise the level of proof for this therapeutic option. The overall prognosis, including quality of life and cost-effectiveness, of HCO hemodialysis should also be examined.

Survival analysis I: the Kaplan-Meier method

The Kaplan-Meier (KM) method is used to analyze 'time-to-event' data. The outcome in KM analysis often includes all-cause mortality, but could also include other outcomes such as the occurrence of a cardiovascular event. The purpose of this article is to explain the basic concepts of the KM method, to provide some guidance regarding the presentation of the KM results and to discuss some important limitations of this method. To do this, we use a clinical example derived from the nephrology literature.

Recurrence of secondary glomerular disease after renal transplantation

The risk of a posttransplant recurrence of secondary glomerulonephritis (GN) is quite variable. Histologic recurrence is frequent in lupus nephritis, but the lesions are rarely severe and usually do not impair the long-term graft outcome. Patients with Henoch-Schonlein nephritis have graft survival similar to that of other renal diseases, although recurrent Henoch-Schonlein nephritis with extensive crescents has a poor prognosis. Amyloid light-chain amyloidosis recurs frequently in renal allografts but it rarely causes graft failure. Amyloidosis secondary to chronic inflammation may also recur, but this is extremely rare in patients with Behcet's disease or in those with familial Mediterranean fever, when the latter are treated with colchicine. Double organ transplantation (liver/kidney; heart/kidney), chemotherapy, and autologous stem cell transplantation may be considered in particular cases of amyloidosis, such as hereditary amyloidosis or multiple myeloma. There is little experience with renal transplantation in light-chain deposition disease, fibrillary/immunotactoid GN, or mixed cryoglobulinemic nephritis but successful cases have been reported. Diabetic nephropathy often recurs but usually only after many years. Recurrence in patients with small vessel vasculitis is unpredictable but can cause graft failure. However, in spite of recurrence, patient and graft survival rates are similar in patients with small vessel vasculitis compared with those with other renal diseases. Many secondary forms of GN no longer represent a potential contraindication to renal transplantation. The main issues in transplantation of patients with secondary GN are the infectious, cardiovascular, or hepatic complications associated with the original disease or its treatment.

Renal Impairment in Patients With Multiple Myeloma: A Consensus Statement on Behalf of the International Myeloma Working Group

Renal impairment is a common complication of multiple myeloma (MM). The estimated glomerular filtration rate (eGFR) using the Modification of Diet in Renal Disease formula is the recommended method for the assessment of renal function in patients with MM with stabilized serum creatinine. In acute renal injury, the RIFLE (risk, injury, failure, loss and end-stage kidney disease) and Acute Renal Injury Network criteria seem to be appropriate to define the severity of renal impairment. Novel criteria based on eGFR measurements are recommended for the definition of the reversibility of renal impairment. Rapid intervention to reverse renal dysfunction is critical for the management of these patients, especially for those with light chain cast nephropathy. Bortezomib with high-dose dexamethasone is considered as the treatment of choice for such patients. There is limited experience with thalidomide in patients with myeloma with renal impairment. Thus, thalidomide can be carefully administered, mainly in the context of well-designed clinical trials, to evaluate if it can improve the rapidity and probability of response that is produced by the combination with bortezomib and high-dose dexamethasone. Lenalidomide is effective in this setting and can reverse renal insufficiency in a significant subset of patients, when it is given at reduced doses, according to renal function. The role of plasma exchange in patients with suspected light chain cast nephropathy and renal impairment is controversial. High-dose melphalan (140 mg/m2) and autologous stem-cell transplantation should be limited to younger patients with chemosensitive disease.

Chronic kidney disease and cancer: a troubling connection

Chronic kidney disease (CKD) and cancer are connected in a number of ways in both directions: cancer can cause CKD either directly or indirectly through the adverse effects of therapies; CKD may, conversely, be a risk factor for cancer; and both may be associated because they share common risk factors, often toxins. In this review, we briefly address the issue of paraneoplastic nephropathies as well as that of toxin-related cancers and CKD, including analgesic and aristolochic acid nephropathies. We then focus on the links between the various stages of CKD and cancer incidence, and critically examine major epidemiologic surveys in the field. Compared with the general population, kidney transplant recipients have a threefold to fourfold increase in overall cancer risk, and relative risks higher than 3 for about 20 specific tumors, most, but not all, of which are known or suspected to be caused by viral agents. After dialysis, cancer risk increases 10% to 80% according to studies, with relative risks significantly higher than in the general population, for about 10 cancer sites. There is emerging evidence for an excess risk of cancer in patients in early CKD stages.