Systemic amyloidosis from A (AA) to T (ATTR): a review.

Systemic amyloidosis is a rare protein misfolding and deposition disorder leading to progressive organ failure. There are over 15 types of systemic amyloidosis, each caused by a different precursor protein which promotes amyloid formation and tissue deposition. Amyloidosis can be acquired or hereditary and can affect various organs, including the heart, kidneys, liver, nerves, gastrointestinal tract, lungs, muscles, skin and soft tissues. Symptoms are usually insidious and nonspecific resulting in diagnostic delay. The field of amyloidosis has seen significant improvements over the past decade in diagnostic accuracy, prognosis prediction and management. The advent of mass spectrometry-based shotgun proteomics has revolutionized amyloid typing and has led to the discovery of new amyloid types. Accurate typing of the precursor protein is of paramount importance as the type dictates a specific management approach. In this article, we review each type of systemic amyloidosis to provide the practitioner with practical tools to improve diagnosis and management of these rare disorders.

Prevalence and predictors of thyroid functional abnormalities in newly diagnosed AL amyloidosis.

BACKGROUND: Data on the effect of systemic immunoglobulin light chain amyloidosis (AL amyloidosis) on thyroid function are limited. OBJECTIVE: To assess the prevalence of hypothyroidism in AL amyloidosis patients and determine its predictors. METHODS: 1142 newly diagnosed AL amyloidosis patients were grouped based on the thyroid-stimulating hormone (TSH) measurement at diagnosis: hypothyroid group (TSH above upper normal reference; >5 mIU L-1 ; n = 217, 19% of study participants) and euthyroid group (n = 925, 81%). Predictors for hypothyroidism were assessed in a binary multivariate model. Survival between groups was compared using the log-rank test and a multivariate analysis. RESULTS: Patients with hypothyroidism were older, more likely to present with renal and hepatic involvement and had a higher light chain burden compared to patients in the euthyroid group. Higher proteinuria in patients with renal involvement and lower albumin in patients with hepatic involvement were associated with hypothyroidism. In a binary logistic regression model, age ≥65 years, female sex, renal involvement, hepatic involvement, kappa light chain restriction and amiodarone use were independently associated with hypothyroidism. Ninety-three per cent of patients in the hypothyroid group with free thyroxine measurement had normal values, consistent with subclinical hypothyroidism. Patients in the hypothyroid group had a shorter survival compared to patients in the euthyroid group (4-year survival 36% vs 43%; P = 0.008), a difference that was maintained in a multivariate analysis. CONCLUSION: A significant proportion of patients with AL amyloidosis present with hypothyroidism, predominantly subclinical, which carries a survival disadvantage. Routine assessment of TSH in these patients is warranted.

Dynamics of melanoma tumor therapy with vesicular stomatitis virus: explaining the variability in outcomes using mathematical modeling.

Tumor selective, replication competent viruses are being tested for cancer gene therapy. This approach introduces a new therapeutic paradigm due to potential replication of the therapeutic agent and induction of a tumor-specific immune response. However, the experimental outcomes are quite variable, even when studies utilize highly inbred strains of mice and the same cell line and virus. Recognizing that virotherapy is an exercise in population dynamics, we utilize mathematical modeling to understand the variable outcomes observed when B16ova malignant melanoma tumors are treated with vesicular stomatitis virus in syngeneic, fully immunocompetent mice. We show how variability in the initial tumor size and the actual amount of virus delivered to the tumor have critical roles on the outcome of therapy. Virotherapy works best when tumors are small, and a robust innate immune response can lead to superior tumor control. Strategies that reduce tumor burden without suppressing the immune response and methods that maximize the amount of virus delivered to the tumor should optimize tumor control in this model system.

Pinhole micro-SPECT/CT for noninvasive monitoring and quantitation of oncolytic virus dispersion and percent infection in solid tumors.

The purpose of our study was to validate the ability of pinhole micro-single-photon emission computed tomography/computed tomography (SPECT/CT) to: 1) accurately resolve the intratumoral dispersion pattern and 2) quantify the infection percentage in solid tumors of an oncolytic measles virus encoding the human sodium iodide symporter (MV-NIS). Sodium iodide symporter (NIS) RNA level and dispersion pattern were determined in control and MV-NIS-infected BxPC-3 pancreatic tumor cells and mouse xenografts using quantitative, real-time, reverse transcriptase, polymerase chain reaction, autoradiography and immunohistochemistry (IHC). Mice with BxPC-3 xenografts were imaged with (123)I or (99)TcO(4) micro-SPECT/CT. Tumor dimensions and radionuclide localization were determined with imaging software. Linear regression and correlation analyses were performed to determine the relationship between tumor infection percentage and radionuclide uptake (% injected dose per gram) above background and a highly significant correlation was observed (r(2)=0.947). A detection threshold of 1.5-fold above the control tumor uptake (background) yielded a sensitivity of 2.7% MV-NIS-infected tumor cells. We reliably resolved multiple distinct intratumoral zones of infection from non-infected regions. Pinhole micro-SPECT/CT imaging using the NIS reporter demonstrated precise localization and quantitation of oncolytic MV-NIS infection, and can replace more time-consuming and expensive analyses (for example, autoradiography and IHC) that require animal killing.

"Real-life" data of the efficacy and safety of belantamab mafodotin in relapsed multiple myeloma-the Mayo Clinic experience.

Belantamab mafodotin is a highly selective targeted therapy for multiple myeloma. It targets the B cell maturation antigen (BCMA) on plasma cells and showed promising results in several randomized clinical trials. We report the outcomes of 36 patients treated at Mayo Clinic. Our cohort received a median of eight prior lines of therapy. Six patients received belantamab in combination with other medications (pomalidomide, cyclophosphamide, thalidomide), 13 patients (36%) were 70 years or older, two patients had a creatinine of >2.5 mg/dL, and one patient was on dialysis. All three patients with renal failure received full dose belantamab. Chimeric antigen receptor (CAR-T) therapy was used prior to belantamab in seven patients and none of them responded to belantamab therapy. The overall response rate (ORR) was 33% (CR 6%, VGPR 8%, PR 19%), like the ORR reported in the DREAMM-2 trial. Keratopathy developed in 16 patients (43%), grade 1 in six patients, grade 2 in seven patients, and grade 3 in three patients. Eight percent discontinued therapy due to keratopathy. The median PFS and OS was 2 months and 6.5 months, respectively.

Cancer phenotype as the outcome of an evolutionary game between normal and malignant cells.

BACKGROUND: There is variability in the cancer phenotype across individuals: two patients with the same tumour may experience different disease life histories, resulting from genetic variation within the tumour and from the interaction between tumour and host. Until now, phenotypic variability has precluded a clear-cut identification of the fundamental characteristics of a given tumour type. METHODS: Using multiple myeloma as an example, we apply the principles of evolutionary game theory to determine the fundamental characteristics that define the phenotypic variability of a tumour. RESULTS: Tumour dynamics is determined by the frequency-dependent fitness of different cell populations, resulting from the benefits and costs accrued by each cell type in the presence of others. Our study shows how the phenotypic variability in multiple myeloma bone disease can be understood through the theoretical approach of a game that allows the identification of key genotypic features in a tumour and provides a natural explanation for phenotypic variability. This analysis also illustrates how complex biochemical signals can be translated into cell fitness that determines disease dynamics. CONCLUSION: The present paradigm is general and extends well beyond multiple myeloma, and even to non-neoplastic disorders. Furthermore, it provides a new perspective in dealing with cancer eradication. Instead of trying to kill all cancer cells, therapies should aim at reducing the fitness of malignant cells compared with normal cells, allowing natural selection to eradicate the tumour.

Impact of additional cytoreduction following autologous SCT in multiple myeloma.

Reported results of high-dose therapy (HDT) reflect the combined effect of initial therapy and HDT. The incremental contribution of HDT is often difficult to analyze with varying degrees of response pre-HDT. Here we analyze results of HDT in patients with measurable disease at transplant, defined as a serum or 24 h urine M protein of >1.0 g per 100 ml and >200 mg per day, respectively. Paraprotein responses were calculated using measurements prior to HDT and the lowest subsequent measurement. A total of 431 patients were studied; 264 (61.3%) transplanted within 1-year of diagnosis. An additional reduction in paraprotein by 50% following HDT was seen in 86% patients; with 129 patients (30%) obtaining a 90% reduction. Patients with at least a 90% reduction had longer time to progression with no overall survival advantage and this was independent of other prognostic factors for decreased risk of progression. This study provides an estimate of the degree of tumor reduction provided by HDT, in addition to that provided by the initial therapy. In this group of patients with measurable disease after initial therapy, HDT therapy leads to complete responses in nearly a quarter of the patients and a 90% reduction in another 7%, an outcome associated with better progression-free survival.

Impact of pretransplant therapy in patients with newly diagnosed myeloma undergoing autologous SCT.

Autologous SCT (ASCT) remains an effective therapy for eligible patients with myeloma. Previous studies have suggested a lack of impact of the initial therapy on the outcome after ASCT. It is not clear if incorporation of new agents in the initial treatment regimens will have any impact on the outcome after ASCT. We studied 472 patients undergoing ASCT within 12 months of diagnosis to assess the effect of initial therapy on the outcome after ASCT. Patients received initial therapy with vincristine, adriamycin and dexamethasone (VAD), dexamethasone, thalidomide and dexamethasone or lenalidomide and dexamethasone. While patients treated with dexamethasone alone had higher disease burden at ASCT, no differences were observed in the response rates to ASCT, post transplant complications or treatment-related mortality among the groups. The median time to progression after ASCT was 27.1, 24.7, 21.1 months and did not reach the VAD, Dex, Thal-Dex and Len-Dex group, respectively, P=0.11. The median overall survival from ASCT was 62 months for VAD, 69.6 months for Dex and were not reached for Thal-Dex and Len-Dex groups, P=0.2. For patients undergoing early ASCT for myeloma, the nature of initial treatment utilized has no long-term impact on the outcome of ASCT.

A practical guide to defining high-risk myeloma for clinical trials, patient counseling and choice of therapy.

Clinical outcomes for multiple myeloma (MM) are highly heterogeneous and it is now clear that pivotal genetic events are the primary harbingers of such variation. These findings have broad implications for counseling, choice of therapy and the design and interpretation of clinical investigation. Indeed, as in acute leukemias and non-hodgkins lymphoma, we believe it is no longer acceptable to consider MM a single disease entity. As such, the accurate diagnosis of MM subtypes and the adoption of common criteria for the identification and stratification of MM patients has become critical. Herein, we provide a consensus high-risk definition and offer practical guidelines for the adoption of routine diagnostic testing. Although acknowledging that more refined classifications will continue to be developed, we propose that the definition of high-risk disease (any of the t(4;14), t(14;16), t(14;20), deletion 17q13, aneuploidy or deletion chromosome 13 by metaphase cytogenetics, or plasma cell labeling index >3.0) be adopted. This classification will identify most of the 25% of MM patients for whom current therapies are inadequate and for whom investigational regimens should be vigorously pursued. Conversely, the 75% of patients remaining have more favorable outcomes using existing - albeit non-curative - therapeutic options.

Elevated pre-transplant C-reactive protein identifies a high-risk subgroup in multiple myeloma patients undergoing delayed autologous stem cell transplantation.

The significance of elevated C-reactive protein (CRP) prior to autologous stem cell transplantation (ASCT) in multiple myeloma (MM) has not been studied. We analyzed 1111 MM patients who underwent ASCT at Mayo Clinic from 2007 to 2015. A total of 840 patients (76%) received early ASCT (⩽12 months from diagnosis) and 271 patients (24%) received delayed ASCT (>12 months from diagnosis). Elevated CRP (> upper normal limit (8 mg/L)) was seen in 14% and 22% of patients undergoing early and delayed ASCT, respectively (P=0.003). There was no correlation of CRP with pre-transplant response, bone marrow plasma cell percentage or labeling index. Patients with an elevated CRP had a higher likelihood of having circulating plasma cells prior to ASCT (33 vs 19%; P<0.001). In the early ASCT cohort, the median overall survival (OS) in patients with normal and elevated CRP was not reached and 91 months respectively (P=0.011). In the delayed ASCT cohort, the median OS in respective groups were 73 and 30 months respectively (P<0.001), with elevated CRP being an independent prognostic marker on multivariate analysis (hazard ratio 2.0; 95% confidence interval, 1.0-3.8; P=0.045). Elevated pre-transplant CRP identifies a high-risk population especially in patients undergoing delayed ASCT and should be incorporated in the pre-transplant evaluation.

Outcomes of maintenance therapy with lenalidomide or bortezomib in multiple myeloma in the setting of early autologous stem cell transplantation.

Post-transplant maintenance is widely used in multiple myeloma (MM); however, there is a lack of data on real-world outcomes. We have analyzed 577 patients with newly diagnosed MM undergoing early auto-transplantation between 2010 and 2015. A total of 341, 132 and 104 patients received no, lenalidomide (Len) or bortezomib (Bort) maintenance, respectively. Patients receiving Len or Bort maintenance had a higher incidence of high-risk cytogenetics by fluorescence in situ hybridization (31% (Len) vs 58% (Bort) vs 8% (No); P<0.001). Len maintenance led to a superior progression-free survival (PFS) compared with no maintenance (median, 37 vs 28 months, respectively; P=0.002; adjusted hazard ratio 0.48 (95% CI, 0.35-0.66)), including in subgroups with ISS stage III disease (median, 40 vs 24 months; P=0.008) and high-risk cytogenetics (median, 27 vs 16 months; P=0.032). Bort maintenance did not confer PFS benefit for the entire cohort, but improved PFS in the high-risk cytogenetic subgroup (median, 28 vs 16 months; P=0.035). Discontinuation due to toxicity was seen in 17 and 7% of patients receiving Len or Bort maintenance, respectively. Our results indicate that post-transplant maintenance with Len or Bort is well tolerated in clinical practice and improves PFS in high-risk subgroups of MM patients.

Pomalidomide-dexamethasone in refractory multiple myeloma: long-term follow-up of a multi-cohort phase II clinical trial.

Despite therapeutic advances, multiple myeloma remains incurable, with limited options for patients with refractory disease. We conducted a large, multi-cohort clinical trial testing various doses and treatment schedules of pomalidomide and dexamethasone (Pom/dex) in patients with refractory multiple myeloma. Overall, 345 patients were enrolled to six cohorts based on number and type of prior lines of therapy, pomalidomide dose and schedule. Median prior lines of therapy were three with near universal prior exposure to proteasome inhibitors and/or immunomodulatory drugs. A confirmed response rate of 35% was noted for all cohorts (range 23-65%) with higher responses in cohorts with fewer prior lines of therapy. Median time to confirmed response was ⩽2 months and the longest progression-free survival and overall survival seen in any cohort were 13.1 and 47.9 months, respectively. Observed adverse reactions were as expected, with myelosuppression and fatigue being the most common hematologic and non-hematologic adverse events (AEs), respectively. Longer durations of treatment and response, higher response rates and fewer AEs were noted with the 2 mg pomalidomide dose. This is the longest follow-up data for Pom/dex in refractory multiple myeloma and will help shape the real-world utilization of this regimen.

Clinical presentation and outcomes in light chain amyloidosis patients with non-evaluable serum free light chains.

Hematologic response criteria in light chain (AL) amyloidosis require the difference in involved and uninvolved free light chains (dFLC) to be at least 5 mg/dl. We describe the clinical presentation and outcomes of newly diagnosed amyloidosis patients with dFLC <5 mg/dl (non-evaluable dFLC; 14%, n=165) compared with patients with dFLC ⩾5 mg/dl (evaluable dFLC; 86%, n=975). Patients with non-evaluable dFLC had less cardiac involvement (40% vs 80%, P<0.001), less liver involvement (11% vs 17%, P=0.04) and a trend toward less gastrointestinal involvement (18% vs 25%, P=0.08). However, significantly higher renal involvement (72% vs 56%, P=0.0002) was observed in the non-evaluable dFLC cohort. Differences in treatment patterns were observed, with 51% of treated patients undergoing upfront stem cell transplantation in the non-evaluable cohort compared with 28% in the evaluable dFLC group (P<0.001). Progression-free survival (61 vs 13 months, P<0.001) and overall survival (OS; 101 vs 29 months, P<0.001) were significantly longer in the non-evaluable dFLC cohort. Normalization of involved light chain levels and decrease in dFLC <1 mg/dl (baseline at least 2 mg/dl) were predictive of OS and associated with better dialysis-free survival and may be used for response assessment in patients with non-evaluable FLC levels.

Natural history of t(11;14) multiple myeloma.

Translocation (11;14) on interphase fluorescent in situ hybridization in plasma cells is regarded as a standard risk prognostic marker in multiple myeloma based on studies conducted before introduction of current therapies. We identified 365 patients with t(11;14), and 730 matched controls:132 patients with non-(11;14) translocations and 598 patients with no chromosomal translocation. The median progression-free survival for the three groups were 23.0 (95% confidence interval (CI), 20.8-27.6), 19.0 (95% CI, 15.8-22.7) and 28.3 (95% CI, 25.7-30.6) months, respectively (P<0.01). The median overall survival (OS) for t(11;14), non-(11;14) translocation and no-translocation groups were 74.4 (95% CI, 64.8-89.3), 49.8 (95% CI, 40.0-60.6) and 103.6 (95% CI, 85.2-112.3) months, respectively (P<0.01). Excluding those with 17p abnormality, the median OS in the three groups were 81.7 (95% CI, 67.0-90.7), 58.2 (95% CI, 47.0-76.4) and 108.3 (95% CI, 92.4-140.1) months, respectively (P<0.01). The above relationship held true in patients with age <65 years, international staging system (ISS) I/II stage or those who received novel agent-based induction. Advanced age (hazard ratio (HR): 1.98), 17p abnormality (HR: 2.2) and ISS III stage (HR: 1.59) at diagnosis predicted reduced OS in patients with t(11;14). These results suggest that outcomes of t(11;14) MM are inferior to other standard risk patients.

Monocytosis is an adverse prognostic factor for survival in younger patients with primary myelofibrosis.

We recently developed a modified Dupriez prognostic scoring system (PSS) that effectively discriminated between high-, intermediate-, and low-risk young patients (age < or =60 years) with primary myelofibrosis (PMF) based on the respective presence of none, one, or two or more of the following parameters: hemoglobin <10 g/dL, leukocyte count <4 or >30 x 10(9)L(-1), and platelet count <100 x 10(9)L(-1). The current study (n=129; median age, 52 years; 69 males) reveals, on multivariable analysis, that an absolute monocyte count of > or =1 x 10(9)L(-1) carries an independent predictive value (p=0.02), for an inferior survival, in addition to that provided by hemoglobin level (p=0.002), platelet count (0.02), and leukocyte count (p=0.16). The inclusion of the monocyte count as a fourth risk factor enabled the construction of a new and improved Mayo PSS; median survival was 173, 61, and 26 months in the absence of all four (low-risk), three (intermediate-risk), or two or less (high-risk) adverse features, respectively (p<0.0001). The independent prognostic value of monocytosis was validated in a separate database of 97 patients with PMF from another institution.

The impact of induction regimen on transplant outcome in newly diagnosed multiple myeloma in the era of novel agents.

We compared overall survival (OS) of 1017 patients with newly diagnosed multiple myeloma (MM) who were treated with different novel agent-based induction regimens and who underwent early autologous stem cell transplant (ASCT). Subgroups were defined by type of induction therapy: cyclophosphamide-bortezomib-dexamethasone (CyBorD; n=193), bortezomib-dexamethasone (Vd; n=64), lenalidomide-dexamethasone (Rd; n=251), bortezomib-lenalidomide-dexamethasone (VRd; n=126), thalidomide-dexamethasone (Td; n=155) and vincristine-doxorubicin-dexamethasone or dexamethasone alone (VAD/Dex; n=228). The median follow-up of the surviving patients was 66.7 months. The 5-year OS rates with CyBorD, Vd, Rd, VRd, Td and VAD/Dex were 79.2%, 72.3%, 79.2%, 79.0%, 57.4% and 63.4%, respectively (log-rank, P<0.001). In a multivariate analysis, after controlling for important patient and disease variables, VRd had a superior OS compared with CyBorD (hazard ratio (HR), 0.32; 95% confidence interval (CI), 0.10-0.88; P=0.03) and Vd (HR, 0.16; 95% CI, 0.04-0.52; P=0.002). In conclusion, our study demonstrates that among patients completing induction therapy and continuing to early transplant, VRd induction leads to improved OS compared with CyBorD and Vd regimens.

Phase I trial of systemic administration of Edmonston strain of measles virus genetically engineered to express the sodium iodide symporter in patients with recurrent or refractory multiple myeloma.

MV-NIS is an Edmonston lineage oncolytic measles virus expressing the human sodium iodide symporter-a means for monitoring by non-invasive imaging of radioiodine. Patients with relapsed, refractory myeloma who had explored all other treatment options were eligible for this Phase I trial. Cohort 1 was treated with intravenous MV-NIS, and Cohort 2 received cyclophosphamide 2 days prior to MV-NIS. Thirty-two patients were treated. Cohort 1 initially enrolled to four dose levels without reaching maximum tolerated dose (MTD) and subsequently to two higher dose levels when improved virus manufacture technology made it possible. MTD was not reached in Cohort 1, and TCID50 1011 is the dose being used in a Phase II trial of single agent MV-NIS. Grade 3-4 adverse events in both cohorts at all dose levels were: neutropenia (n=9); leukocyte count decreased (n=5); thrombocytopenia (n=2); and CD4 lymphocytes decreased, anemia and lymphopenia (each n=1). MV-N RNA sequences were amplified from gargle specimens, blood and urine. 123I scans were positive in eight patients. One patient achieved a complete response; transient drops in serum free light chains were seen in other patients. MV-NIS is capable of replicating before being cleared by the immune system. Oncolytic viruses offer a promising new modality for the targeted infection and destruction of disseminated myeloma.

Immunoparesis in newly diagnosed AL amyloidosis is a marker for response and survival.

Immunoparesis is an adverse prognostic marker in plasma cell proliferative disorders. Its impact in AL amyloidosis has not been explored in depth. Newly diagnosed AL amyloidosis patients (n=998) were evaluated for immunoparesis by two methods. The first method was qualitative, considering the number of suppressed uninvolved immunoglobulins below the lower limit of normal (LLN) (none, partial, all). The second method was quantitative, assessing the average relative difference (ARD) of the uninvolved immunoglobulins from the LLN. Patients with suppression of all the uninvolved immunoglobulins were less likely to achieve very good partial response (VGPR) or better to first-line treatment (44%) compared with patients with partial suppression (68%) or preserved uninvolved immunoglobulins (64%; P<0.0001). In addition, patients with suppression of all the uninvolved immunoglobulins had a shorter survival compared with the respective comparators (median 18 vs 54 vs 52 months; P<0.0001). In the quantitative method, patients with a negative ARD were less likely to achieve VGPR or better (48%) and had a shorter survival (median 24 months) compared with patients with a positive ARD (69%, 57 months, respectively; P<0.0001). In a multivariate analysis for survival, both assessment methods retained an independent impact. Significant immunoparesis has a negative impact on response and survival in newly diagnosed AL amyloidosis.