The prognostic significance of polyclonal bone marrow plasma cells in patients with relapsing multiple myeloma

Prior studies have revealed that the presence of increasing number of polyclonal plasma cells (pPCs) in the bone marrow (BM) are associated with better outcomes in newly diagnosed multiple myeloma (MM) patients. This effect has not been studied in patients with MM at the time of disease relapse. We determined the prognostic value of depletion of pPCs in the BM by 7-color multiparameter flow cytometry in a series of 174 relapsing MM patients. The time to next therapy (TTNT) in those with <5% pPCs was 9.4 months versus 13.9 months in those with ≥5% pPCs (P = .0091). The median overall survival (OS) in those with <5% pPCs was 21.4 months, while the median OS was not reached in those patients with ≥5% pPCs (P = .019). Of the 109 patients with standard risk cytogenetics, the median OS of those with <5% pPCs was 28.4 months, while the median OS was not reached in those with ≥5% pPCs (P = .033). As such, <5% pPCs in the BM appears to have prognostic utility in identifying a subset of relapsing MM patients, even with standard-risk cytogenetics, who have a particularly adverse outcome.

Predictors of early treatment failure following initial therapy for systemic immunoglobulin light-chain amyloidosis

We analysed factors predicting early treatment failure (ETF), after first-line therapy for light-chain amyloidosis (AL). AL amyloidosis patients seen at Mayo Clinic within 90 days of diagnosis, from 2006 to 2015, excluding those who died within 3 months of initial therapy, were analysed retrospectively. ETF was defined as progression requiring treatment change or death within 12 (ETF12) or 24 (ETF24) months of first-line treatment. Non-ETF included those with a follow-up of more than 12 or 24 months who had progression beyond 12 or 24 months. A total of 724 patients met the study criteria; 244 (33.7%) had ETF12 and 388 (53.6%) had ETF24. Patients with ETF12 were older (64.1 vs. 62.2 years) with higher prevalence of cardiac (81 vs. 64.1%) and multi-organ involvement (67.2 vs. 45.4%) and higher proportion of patients with t(11; 14) (58.5 vs. 44.3%) or in higher Mayo 2012 stage (58.5 vs. 41.1%).The median follow-up was 5.4 years from start of initial therapy. In multivariate analysis, presence of t(11; 14) and non-incorporation of autologous transplant in initial therapy are significant predictors of ETF12 (p = .01and p = .003) and ETF24 (p = .0001 and p = .005) while Mayo stage is predictive of ETF24 (p = .002), but not ETF12.

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.

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.

Elevation of serum lactate dehydrogenase in AL amyloidosis reflects tissue damage and is an adverse prognostic marker in patients not eligible for stem cell transplantation

The significance of serum lactate dehydrogenase (LDH) in light chain (AL) amyloidosis has not been previously explored. We studied 1019 newly diagnosed patients and correlated the elevation of LDH above the upper limit of normal (ULN) with disease characteristics and outcome. Four hundred and nine patients had an LDH above ULN, representing 40% of the study population. Patients with an elevated LDH were older, were less likely to be male and had more extensive organ involvement compared to patients with a normal LDH. Patients with high LDH had greater cardiac and renal dysfunction. Elevated LDH was an independent prognostic marker for overall survival and for death within 6 months of diagnosis, but this was restricted to patients not eligible for stem cell transplant. Serum LDH may act as a marker for organ damage and should be explored as a potential marker for tissue healing and organ recovery.

Clinical presentation and outcomes of patients with type 1 monoclonal cryoglobulinemia

We describe a series of 102 patients diagnosed from January 1, 1990 to December 31, 2015 with Type 1 monoclonal cryoglobulinemia (MoC). Symptoms were seen in 89 (87%) patients, including: cutaneous symptoms in 64 (63%) patients, with purpura (n = 43, 42%) and ulcers/gangrene (n = 35, 34%) being most common; neurological findings in 33 (32%) patients, most frequently sensory neuropathy (n = 24, 24%); vasomotor symptoms, mainly Raynaud's phenomenon in 25 (25%); arthralgias in 24 (24%); and renal manifestations, primarily glomerulonephritis in 14 (14%) patients. An underlying lymphoproliferative disorder was identified in 94 (92%) subjects; MGUS-39, myeloma-20, lymphoplasmacytic lymphoma-21 and others-14. Treatment was initiated in 73 (72%) patients, primarily for cryoglobulinemia-related symptoms in 57. Treatment regimens consisted of: steroids ± alkylating agents in 29 (40%), novel myeloma therapies in 16 (22%), rituximab with alkylating agents in 12 (16%) and rituximab ± steroids in 11 (15%) patients; 22 patients received plasmapheresis. Six patients underwent autologous stem cell transplant. Cryocrit at treatment initiation, change in cryocrit and time to nadir cryocrit were predictive of symptom improvement. Treatment directed toward the underlying clonal disorder resulted in improvement (n = 47) or stabilization (n = 16) of symptoms in the majority of patients and disappearance of cryoglobulin in over one-half.

Treatment patterns and outcome following initial relapse or refractory disease in patients with systemic light chain amyloidosis

We analyzed the outcomes following initial relapse or refractory disease in systemic light chain amyloidosis (AL) and the impact of type of therapy employed.A total of 1327 patients with AL seen at Mayo Clinic within 90 days of diagnosis, between 2006 and 2015, were reviewed. The study included 366 patients experiencing a documented hematological or organ relapse or refractory disease requiring start of second line therapy. Overall survival (OS) and time to next treatment (TTNT) were calculated from start of second line treatment.The median time to require second line treatment was 16.2 months (1-93) from the start of first line therapy. At relapse, patients received proteasome inhibitors (PI; 45.1%), immunomodulators (IMiD; 22.7%), alkylators (9%), PI and IMiD combination (4.1%), autologous transplant (3.8%), steroids and other therapies (4.9%). Among these, 124 (33.9%) required change or reinstitution of therapy. The median time to require third line treatment was 31 months (95% CI; 24, 40.5) and the median overall survival (OS) was 38.8 months (95% CI; 29.6, 52.6) from the start of second line treatment. Retreatment with same therapy at relapse significantly reduced TTNT (22 m vs 32.3 m; P = .01) as compared to different therapy; but did not have any impact OS (30.8 m vs 51.1 m; P = .5). In conclusion, this study provides important information about outcomes of patients with AL who require second line treatment for relapsed/refractory disease . Treatment with a different therapy at relapse improves time to next therapy but does not impact OS.

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.

Presentation and Outcomes of Localized Immunoglobulin Light Chain Amyloidosis: The Mayo Clinic Experience

OBJECTIVE

To describe treatment types, outcomes, and relapse patterns in patients with localized immunoglobulin light chain amyloidosis (AL_L).

PATIENTS AND METHODS

We included all patients with AL_L seen at Mayo Clinic in Rochester, Minnesota, from January 1, 1968, through June 30, 2014. The diagnosis of AL_L was predicated on the presence of a Congo red-positive biopsy specimen and negative serum and urine immunofixation. Treatment response categories were response, stability, and progression. Localized and systemic progressions were defined as progression of disease at the site of origin or appearance of clonal plasma cells in a bone marrow biopsy sample, respectively.

RESULTS

Of 5551 patients with AL, 413 (7%) had AL_L. The most common site involved was urothelial tissue (n=85, 21%), followed by the larynx (n=57, 14%). Coexisting autoimmune diseases were reported in 7% of patients (n=28). The most common first-line treatment was excision of the amyloid deposits (61%), followed by observation or supportive care (28%). When considering symptomatic patients only (n=284), 205 (72%) improved, 23 (8%) had stable disease, and 55 (19%) could not be evaluated for response. Ten-year survival was 78% and was not different from that of the general population. There were no systemic progressions, but 17% of patients (n=72) had localized progression.

CONCLUSION

Localized AL is associated with a relatively distinct pattern of organ involvement. The initial laboratory evaluation to exclude systemic disease could be limited to serum and urine immunofixation in most patients. Recurrence after first-line therapy is common, but long-term outcomes are excellent.

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

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Background: t(11;14) is a standard risk cytogenetic marker in MM. Methods: We reviewed 366 patients with MM who had t(11;14) by FISH and 732 age and period-matched controls without t(11;14), seen at our institution from 2004 to 2014 and outcomes were analyzed using time to first progression or death (PFS1) and overall survival (OS). Results: For the t(11;14) group at diagnosis, the median age was 63.7 yr (range, 22.1-95.4) with 64.5% of patients being male. Eighty nine (24.3%) patients were above 70 yr of age at diagnosis. 33.8%, 40.3% and 25.9% patients belonged to ISS 1, II and III stages respectively. 13% patients had elevated LDH. Monosomy 17 or del 17p were identified in 10.6% patients. The median follow up period was 56.9 months (m) (95% CI: 54.6-62.2) and 209 (57.1%) patients were alive at last follow-up. Among patients receiving proteasome inhibitor (PI)-based, immunomodulator (IMiD)-based, PI+IMiD based or other agent based induction therapy, 71.2%, 70.3%, 90.4% and 37.5% patients respectively attained ≥PR as best response to induction (p < 0.01). During their course, 223 (60.9%) patients underwent stem cell transplant. Median PFS1 and OS were 23.1 (CI: 20.8-27.9) and 78.6 (CI: 66.7-105.9) m respectively. Among the controls, high risk cytogenetics (HRC) was present in 142 (19.4%), and the median OS was 83.8 m (CI: 70.8-97.0) being comparable to t(11;14) group (p = 0.8). For all 1098 patients, using a Cox-proportional hazards model with age > 70 years, induction therapy (novel agent-based vs others), cytogenetics [HRC vs t(11;14) without HRC vs no HRC or t(11;14)], and ISS stage III vs II/I as predictors, age > 70 years [HR-2.2 (CI: 1.8-2.8) and p < 0.01], ISS III vs ISS II/I [HR-1.4 (CI: 1.1-1.8) and p < 0.01] and HRC [HR of 2.1 (CI: 1.6-2.8) vs no HRC or t(11;14) (p < 0.01) and 1.9 (CI = 1.4-2.6) for t(11;14) without HRC (p < 0.01)were associated with reduced OS. The risk for reduced OS did not differ between t(11;14) without HRC, and those without t(11;14) or HRC [HR-1.1 (CI: 0.9-1.4), p = 0.4]. Conclusions: Our study characterizes the outcomes of a large cohort of MM patients with t(11;14) at diagnosis. Advanced age, HRC and advanced stage at diagnosis were associated with worse OS in our cohort. t(11;14) MM without HRC does not differ in outcome compared to non-t(11;14) MM without HRC.

The impact of body mass index on the risk of early progression of smoldering multiple myeloma to symptomatic myeloma

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Background: Human adipocytes can contribute directly to the in vitro growth and progression of multiple myeloma (MM) cell lines. Clinically, an elevated body mass index (BMI) has been associated with an increased risk of MGUS and a shorter time to progression (TTP) of MGUS to MM. However, the impact of BMI on the risk of early progression to MM from a more advanced plasma cell disorder such as smoldering MM (SMM) remains unknown. Methods: This study included patients (pts) with a known or new diagnosis of SMM evaluated at the Mayo Clinic, Rochester from January 2000-December 2010. Pts were classified based on their BMI as: normal (< 25) and elevated (>/= 25) BMI. Progression to symptomatic MM was defined by the development of hypercalcemia, renal insufficiency, anemia or lytic bone lesions. Results: There were 306 pts with a diagnosis of SMM who were included in this analysis. The median follow up was 106 months. There were 203 (66%) pts who progressed to symptomatic MM at last follow up. The median BMI of the group was 27.5 (Range: 17.2 – 56.4). There were 228 (75%) pts with an elevated BMI. There were 76 (28%) pts who had myeloma defining events (MDEs) such as a serum free light chain ratio > 100 or > 60% clonal bone marrow plasma cells at initial evaluation. MDEs were present in 17% and 33% of pts with a normal and elevated BMI respectively (P = 0.011). The median TTP of SMM to MM in pts with a normal and elevated BMI was 64 and 36 months respectively (P = 0.0006). The 2-year progression rate of SMM to symptomatic MM in pts with a normal and elevated BMI was 16% and 42% respectively (P < 0.0001). Upon limiting the analysis to only SMM pts without MDEs at initial evaluation (N =187), the 2-year progression rate to symptomatic MM with a normal and elevated BMI was 15% and 33% respectively (P = 0.013). In a multivariable model, only elevated BMI (P = 0.004) and increasing clonal bone marrow plasma cells (P = 0.001) was statistically significant in predicting for a 2-year progression to MM. Conclusions: SMM pts with an elevated BMI appear to have a higher risk of early progression to MM than those with a normal BMI. This study provides evidence of a potentially modifiable risk factor for the progression of SMM to MM and warrants confirmation in larger studies.

Risk stratification by detection of clonal circulating plasma cells (CPCs) by multi-parametric flow cytometry (MFC) in light chain amyloidosis (AL)

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Background: Presence of CPCs by six color MFC is associated with worse outcomes in multiple myeloma (MM). Using a slide based immunofluorescence assay, CPCs are associated with worse prognosis in AL, but outcomes with MFC are not known. Methods: We retrospectively analyzed 154 patients (pts) from Jan 2008 – Dec 2015 with AL who had CPCs analyzed by MFC at diagnosis. Results: CPCs were present in 42% pts (n = 64, median = 88 per 150,000 events, range 6-17844). Table 1 lists baseline characteristics, treatment and response. In univariate analysis, bone marrow (BM) plasma cells > 15% (p<0.0001), dFLC > 60 mg/dL (p=0.02) and presence of active MM (p=0.0004) were associated with detectable CPCs. In multivariate (MV) model, only BM plasma cells > 15% predicted for presence of CPCs (p=0.02). There was no difference in hematologic or organ response in the 2 groups. Median follow up was 43 months (m). Pts with detectable CPCs had worse survival than those without detectable CPCs (90 m vs. 98 m, p=0.0004). In MV analysis model with Mayo Stage and detectable CPCs, presence of CPCs at diagnosis was independently associated with poor survival (CPCs p= 0.02, Mayo Stage p < 0.0001). Conclusions: Presence of detectable CPCs is an independent adverse prognostic factor for survival in AL. Comparatively fewer pts with detectable CPCs underwent early ASCT, which may reflect a more aggressive disease presentation. [Table: see text]

Daratumumab-based combination therapies (DCT) in heavily-pretreated patients (pts) with relapsed and/or refractory multiple myeloma (RRMM)

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Background: Daratumumab-based Combination Therapies (DCT) with bortezomib (V)/ lenalidomide (R)/ pomalidomide (P) and dexamethasone (d) showed exceptional activity in RRMM in trials. Experience outside of trials since the approval of Daratumumab (D) in 2015 is limited. Methods: RRMM pts seen at Mayo Clinic, MN from 12/2015 -12/2016 were reviewed. Pts who received ≥ 1cycle of DCT were included. Time-to-event analyses were done from date of starting DCT. Common terminology criteria for adverse events v4.0 were used to grade toxicities. Results: Of 130 pts, 59% were males and median age at DCT initiation was 67 (43-93) years, ECOG performance score was ≥2 in 29%. Pts were classified as mSMART high (22%), intermediate (22%) or standard (56%) risk. Median time from diagnosis to initiation of DCT was 51.3 (5-156) months (m), and median number of prior therapies was 4 (1-14). 14% of pts were refractory to prior D monotherapy. Fifty-three (41%), 34 (26%) and 25 (19%) received DPd, DRd and DVd respectively. Eighteen (14%) pts received ‘other’ DCT. Median time to first response (≥ PR) was 3.1 m (95% CI 2.1-4.6). Overall response rate was 46%, [CR-2%, VGPR-18%, PR-26%]. Minimal response was seen in 17%, with clinical benefit rate of 62%. Median estimated follow up from initiation of DCT was 5.5 m (CI 4.2-6.1). The median duration of response was 6.1 m [CI 5.1- not reached (NR)]. Median progression free survival (PFS) was 5.5 m (CI 4.1-7.8) and median time to next therapy (TTNT) was 5.9 m (CI 4.6-9.4). Median PFS for DPd, DRd, DVd and other DCTs were 4.6 (CI 2.7-NR), 7.8 (CI 5-NR), 3.9 (CI 2.1-NR) and 3.9 (CI 2.8-8.2) m, respectively (p = 0.3). Median PFS for quadruple refractory (n = 28) MM was 2.8 m (CI 2.2-5.3) vs 5.9 m (CI 4.9-NR) for the rest (p < 0.01). Median overall survival (OS) from DCT was NR (CI 11.4-NR). Grade 3 or higher hematological toxicities were seen in 42% of pts. Other toxicities included infections (37%), fatigue (31%), infusion reactions (16%) and diarrhea (10%). Conclusions: DCT are effective in RRMM, but the PFS remains short particularly in quadruple refractory pts, reflecting the challenges encountered in managing heavily-pretreated, and often less fit patients, in routine practice.

Prognostic impact of kinetics of circulating plasma cells before and after induction therapy in newly diagnosed multiple myeloma patients undergoing early transplantation

8020

Background: Circulating plasma cells (CPCs) at diagnosis, prior to transplant and at relapse have a negative prognostic impact on survival in multiple myeloma (MM). However, the impact of changes in CPCs along the course of illness has not been defined. Methods: We evaluated 247 patients with newly diagnosed MM (NDMM) undergoing early autologous stem cell transplantation (ASCT) in the era of novel agents (2007 to 2015), who had serial evaluation of CPCs at diagnosis and pre-ASCT by 6-color flow cytometry. Results: The median age at transplant was 62 years.A total of 117 (47%) patients had no detectable CPCs at both time points (CPC-/-), 82 (33%) had CPCs at diagnosis followed by complete eradication after induction therapy (CPC+/-) and 48 (19%) had detectable clonal CPCs at transplant, with persistence of cells (CPC+/+; n=45) or emergence of new CPCs (CPC-/+; n=3) after induction. The incidence of t(11;14) by iFISH was lower in the CPC-/- group (19%) compared to CPC+/- (29%) and CPC +/+ or -/+ (39%) groups ( p=0.033). Conversely, the incidence of hyperdiploidy was significantly higher in patients with CPC-/-, compared to those with CPC+/- and CPC+/+ or -/+ (64%, 44% and 39% respectively; p=0.005). The rate of post-ASCT stringent complete response was 32% in the CPC-/- group, 30% in CPC+/- group and 12% in CPC+/+ or -/+ group ( p=0.018). At a median follow-up of 58 months from ASCT, the median progression-free survival (PFS) from transplant in the 3 respective groups was 30, 24 and 14 months and the 5-year overall survival (OS) rates were 83%, 70% and 43% ( p<0.001 for both comparisons). On a multivariate analysis, using CPC-/- group as the comparator, PFS and OS was significantly inferior in CPC+/- (RR 1.6; p=0.020 and RR 2.7; p=0.008 for PFS and OS respectively) and CPC +/+ or -/+ groups (RR 2.9; p<0.001 and RR 5.8; p<0.001 for PFS and OS respectively). Conclusions: Clonal CPCs are detectable in more than 50% of newly diagnosed MM patients undergoing upfront ASCT. Monitoring for CPCs before initiation of induction therapy and before ASCT by 6-color flow cytometry is highly predictive of outcome in NDMM and should be incorporated into prospective clinical trials.

Outcomes according to involved free light chain (FLC) levels in patients with normal FLC ratio after initial therapy in light chain amyloidosis (AL)

8049

Background: Complete response in AL is defined as normal FLC ratio with negative serum and urine immunofixation. It is not clear if high involved serum FLC (hIFLC) in a patient with normal ratio may contribute to ongoing amyloid formation and hence affect outcomes. Methods: Data of 1308 patients (pts) with systemic AL seen within 90 days of diagnosis, at Mayo Clinic between 2006-2015, was analyzed retrospectively. Among these, 369 pts had 2 consecutive normal FLC ratio values after 1st line treatment and form the study population. Log rank test was used to estimate survival differences. Results: Among these 369 pts, pts with hIFLC at 1streading of normal FLC ratio (hIFLC1; n=170; 46.1%) were compared to those who did not (n=199; 53.9%). At diagnosis, the median age [61.5 vs 60.8 years (y); p=0.2], proportion of males (62.4 vs 58.3%; p=0.4), percentage of pts with renal involvement (73.5 vs 64.8%; p=0.07), in mayo stage I / II / III / IV (32.9% / 23%/ 27.3% / 16.8% vs 43.6 %/ 22.9% / 18.1% / 15.4%; p=0.1), with bone marrow plasma cells >10% (24.2 vs 30%; p=0.2) and with presence of t(11; 14)(48.4 vs 60; p=0.08) was similar, while cardiac (67.5 vs 53.3%; p=0.006) and hepatic (18.2 vs 9.1%; p=0.01) involvement was higher in hIFLC1 group. The median follow-up from diagnosis was 6.1 y (95% CI; 5.6, 6.8). The median progression free survival (PFS) in pts who had hIFLC1 was lower than for those who did not; 2.6 y (95% CI; 1.9, 4.5) vs 5.2 y (95% CI; 4.6, 6.4), p<0.0001, as was the median overall survival [OS; 6.7 y (95% CI; 4.5, 8.3) vs not reached (NR), p<0.0001]. We performed a more stringent comparison for pts with 2 consecutive hIFLC values (hIFLC2; n=112; 30.4%) versus not (n=257; 69.6%). The median PFS (3.2 y; 95%CI; 2.2, 4.5 vs 5.6 y; 95% CI; 4.7, 7.1; p<0.0001) and OS (7.8 y; 95% CI; 6.4, NR vs NR; 95%CI; 9.5, NR; p<0.0001) were significantly reduced in pts with hIFLC2 versus not as well. A multivariate analysis confirmed an impact of hIFLC1 and hIFLC2 on PFS/OS independent of serum creatinine. Conclusions: In pts with systemic AL, persistent elevation of the involved FLC predicts for poor prognosis (independent of serum creatinine) even among those who achieved normal FLC ratio after 1st line treatment.

Overuse of organ biopsies in immunoglobulin light chain (AL) amyloidosis: The consequence of failure of early recognition

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Background: The diagnosis of amyloidosis requires histological confirmation of Congo-red (CR) deposits. The tissue source is preferably fat and/or bone marrow biopsy, but at times organ biopsy is required. Methods: We studied 612 patients with systemic light chain amyloidosis to characterize the tissues used to establish the diagnosis Results: The median number of tissue samples biopsied for CR staining was 3. Ninety-five percent of bone marrow (BM) biopsies were stained for CR, while 79% of patients had fat aspiration performed for CR staining. Overall, 76% of patients underwent both procedures. CR stain sensitivity was 69% in BM samples, 75% in fat aspiration and in 89% for both sources combined. CR stain sensitivity was 97-100% for heart, renal and liver biopsies. 42% of patients with renal involvement, 21% of patients with liver involvement and 13% of patients with heart involvement underwent organ biopsy, when a less invasive safer biopsy would have established the diagnosis. Predictors of need for organ biopsy were male sex, limited organ involvement and lack of fat aspiration (Table). Conclusions: Fat aspiration is underutilized for histologic confirmation of amyloidosis. Organ biopsies (particularly renal biopsies) were performed at a high rate, which represents a failure to recognize the disease (i.e. failure to screen with a light chain assay etc.). Early awareness of amyloidosis in the differential diagnosis of patients with organ dysfunction may lead to fewer unnecessary organ biopsies [Table: see text]

Impact of metformin use in the outcomes of multiple myeloma patients post stem cell transplant

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Background: Multiple myeloma (MM), a monoclonal plasma cell disorder, is one of the most common hematologic malignancies in the US. In preclinical studies, metformin demonstrated plasma cells cytotoxicity. However, there is lack of studies translating the effect of metformin into the clinical setting. Therefore, we assessed the clinical effect of metformin in patients (pts) with MM. Methods: All MM pts who underwent stem cell transplant (SCT) at the Mayo Clinic Rochester from 2007 to 2012 were reviewed. Patients were grouped based on metformin use. Initial diagnosis at our institution and ≥12 months of follow up were required. Kaplan-Meier method and Cox regression were used for time-to-event and multivariate analysis. Results: Out of 687 pts, 78 (11.4%) were using metformin at the time of MM diagnosis. Baseline characteristics in the metformin (Mt) and no-metformin (NMt) groups were similar (Table). Median (M) metformin dose was 2000 mg daily and m duration of metformin use from MM diagnosis was 22 months. Pts on the Mt group achieved higher rates of CR after SCT (41% vs. 29%, p<0.02). Median PFS after SCT was longer in the Mt group, 31.3 months (95% CI: 10.4-52.2) vs. 16.6 months in the NMt group (95%CI: 14.5-18.7) p<0.04. There was a trend towards longer OS in the Mt group, but it was not statistically significant (170 vs. 106 months, p<0.10). In a multivariate analysis of metformin use, age, ISS, LDH, and cytogenetics/FISH, the former was an independent predictor of PFS after SCT (OR: 0.38, 95%CI: 0.20-0.68, p<0.001). Conclusions: Metformin use was associated with a better PFS and higher CR after SCT in our MM cohort. A trend towards better OS was also noted in the Mt group. Larger studies are needed to enhance our understanding of the clinic effect of metformin on MM. [Table: see text]

The use of proteasome inhibitors among patients with POEMS syndrome

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Background: Neuropathy is a universal symptom of patients with POEMS syndrome, which makes the use of bortezomib less appealing. However, proteasome inhibitors (PIs) can provide rapid and deep hematologic responses in plasma cell disorders. Because there is very little data regarding the use PIs in POEMS syndrome, we performed a study of patients with POEMS syndrome treated with PIs. Methods: Among the 167 patients with POEMS syndrome seen at our institution between 2001-2016, we identified 12 patients who received a PI. One patient receiving < 1 cycle of bortezomib because of worsening neuropathy was included but was excluded from response analyses. One patient received 2 different PIs at separate points during the disease course and each course was considered separately. Four response categories were considered: hematologic, PET, VEGF and clinical as previously described (Dispenzieri et. al AJH 2015). Results: Among the 12 patients who received 13 courses of therapy, the median age at PI initiation was 59; 8 patients were male. Median number of prior therapies was 1 (0-4) and median time from diagnosis to initiation of PI was 75 months. Excluding steroids, regimens were as follows: bortezomib, n=3; bortezomib and cyclophosphamide, n=4; carfilzomib, n=1; and ixazomib, n=1. With a median follow-up from PI initiation of 18 months, the median duration of treatment was 7 months (1-18). Three patients achieved a hematologic CR. Of 6 patients with an abnormal baseline VEGF, 3 achieved normalization VEGF levels. Of 5 patients with an abnormal baseline PET, 2 achieved normalization of their PET. Two patients had improvement of their neuropathy, with the rest having stable symptoms. Of 9 patients with fluid overload, 8 improved. Only 2 patients stopped therapy due to worsening neuropathy related to PIs. Median PFS and OS from initiation of PI were 50 months and 53 months, respectively. Conclusions: We show that PI use in patients with POEMS syndrome can be safe and effective. Nearly 75% of patients treated with bortezomib had no exacerbation of their neuropathy. Clinical improvement in severe fluid overload symptoms (edema, ascites, pleural effusions) is almost universal, making PI-based therapy an attractive potential option in these patients.

Factors predicting organ response in light chain amyloidosis (AL)

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Background: Organ response (OR) in AL is often delayed and difficult to predict early. Methods: We retrospectively analyzed 1308 patients (pts) with newly diagnosed AL from 2006 – 2015 to determine factors which could predict for OR. Results: Median age was 64 years (yr) and Mayo Stage was: 1 (22%); 2 (23%); 3 (25%); 4 (31%). Organ involvement was: cardiac (74%, n=932); renal (59%, n=738), liver (16%, n=205); gut (24%, n=310) and autonomic (12%, n=152). 59% (n=765) had > 1 organ involved, including 43% (n=567) with > 1 critical organ (heart, kidney, liver) involved. Treatment was: ASCT based (28%, n=330, N=1186), bortezomib based (24%, n=281), alkylator based (33%, n=392), others (5%, n=54) and none (10%). In evaluable pts, VGPR or better rates were: 53% at 6 months (m) (N=625), 72% at 12 m (N=465) and 57% overall (N=688). Table 1 lists OR at various time points. Complete OR in all involved critical organs was seen in: 51% (n=308, N=600), partial response (at least 1 OR when >1 organ involved) in 12% (n=73) and none in 37% (n=219). Complete OR was associated with better overall survival (OS) than partial or no OR (median OS: not reached vs 42 m vs 29 m; P <0.0001). In multivariate model the following variables at baseline or 1 yr mark were predictive of complete OR: lower Mayo Stage (p=0.01), fewer critical organs involved (p=0.007), higher baseline GFR (p=0.03), female sex (Complete OR 60% vs 47%; p=0.04) and VGPR at 1 yr (Complete OR 70% vs. 36%; p <0.0001). Other factors included in the model were age (p=0.9), bilirubin (p=0.1) and transplant (p=0.2). All aforementioned factors were significant in univariate analysis. Conclusions: Achievement of response in all involved critical organs is associated with better survival in AL pts than partial or no OR. Various baseline factors and VGPR at 1 yr can predict for achieving complete OR, with 70% pts who achieve VGPR at 1 yr having a complete OR. [Table: see text]

Serial measurements of circulating plasma cells before and after induction therapy have an independent prognostic impact in patients with multiple myeloma undergoing upfront autologous transplantation

Circulating plasma cells at diagnosis, prior to auto-transplant and at relapse have a negative impact on survival in multiple myeloma. However, the impact of kinetics of circulating plasma cells along the course of illness has not been defined. We have analyzed 247 newly diagnosed multiple myeloma patients undergoing early auto-transplant who had paired evaluation of circulating plasma cells at diagnosis and pre-transplant by 6-color flow cytometry. A total of 117 patients had no detectable circulating plasma cells at both time points (CPC−/−), 82 had circulating plasma cells at diagnosis followed by complete eradication after induction (CPC+/−) and 48 had circulating plasma cells at transplant, including persistence of cells (CPC+/+; n=45) or emergence of new cells (CPC−/+; n=3) after induction. The rate of post-transplant stringent complete response was 32% in the CPC−/−, 30% in CPC+/− and 12% in CPC+/+ or −/+ groups (P=0.018). At a median follow up of 58 months from transplantation, the median progression-free survival in the 3 respective groups were 30, 24 and 14 months, and the 5-year overall survival rates were 83%, 70% and 43% (P<0.001 for both comparisons). On a multivariate analysis for overall survival, the risk of mortality was higher in CPC +/− (hazard ratio 2.7, 95%CI: 1.3–5.8; P=0.009) and CPC+/+ or −/+ (hazard ratio 5.7, 95%CI: 2.5–13.1; P<0.001) groups compared to the CPC−/− group. Monitoring for circulating plasma cells before induction therapy and before transplant by 6-color flow cytometry is predictive of survival in newly diagnosed myeloma and should be incorporated into clinical trials.

Hematology patient reported symptom screen to assess quality of life for AL amyloidosis

Patients with light chain amyloidosis (AL) often have delayed diagnosis and present with significant symptomatology; this may result in decreased quality of life (QOL). We prospectively employ a "Hematology Patient Reported Symptom Screen" (HPRSS), which is three questions about fatigue, pain, and QOL, scored 0-10. The aim of this study is to better understand QOL and determine if HPRSS parameters predict for clinical outcomes. From 2009 to 2014, 302 newly diagnosed AL patients were included. Baseline median scores [interquartile range] for fatigue, pain, and QOL were 6 [3,7], 2 [0,5], 5 [3,8], respectively. Median overall survival was 53 months, with 102 (34%) deaths in the first year. There were significant differences in baseline HPRSS between those that lived longer than one year and early death patients in the domains of fatigue (5 [IQR 3, 7] vs. 7 [IQR 5, 8], P < 0.0001) and QOL (6 [IQR 4, 8] vs. 5 [IQR 3, 7], P = 0.006). On univariate analysis fatigue, QOL, physician-reported performance status, autologous stem cell transplant (ASCT), and Mayo stage were prognostic for survival. On multivariate analysis Mayo stage, ASCT, and baseline fatigue remained independently prognostic. When analyses were restricted to the 125 patients with HPRSS measurements at 12 months, we found that over time QOL scores improved significantly 6 [IQR 3.5, 8] → 7 [IQR 5, 8] (P = 0.01). Asking AL patients to rate their fatigue and QOL has predictive value. Baseline patient reported fatigue is an independent prognostic factor for survival. Survival at one year was associated with significant improvement in QOL.