Incidence of second primary malignancies in patients with multiple myeloma receiving anti-CD38 monoclonal antibodies: A systematic review and meta-analysis.

Anti-CD38 monoclonal antibodies (mAbs) are commonly used for treating newly diagnosed and relapsed/refractory (r/r) multiple myeloma (MM). However, concerns have been raised about the occurrence of second primary malignancies (SPMs) in patients receiving anti-CD38 mAbs. Assessing the safety data for rare adverse events like SPMs is challenging because individual clinical trials are typically focused on the primary endpoint. Therefore, we conducted a meta-analysis of randomized controlled trials (RCTs) published between January 2005 and April 2022, including patients with newly diagnosed or r/r MM. Our aim was to compare SPM rate with the use of anti-CD38 mAb-based regimens with other anti-myeloma regimens. After a median follow-up of 35.3 months (range: 8.2-56.2), we found that exposure to anti-CD38 mAbs was associated with an increased risk of developing SPMs compared to the control group (6.8% vs. 5.2%; Peto odds ratio [OR]: 1.53 [95% confidence interval (CI): 1.20-1.95]; I2= 0%, p-value for heterogeneity= 0.44). This increased risk was primarily driven by non-melanoma cutaneous cancers (92 vs. 47; Peto OR: 1.77 [95% CI: 1.25-2.51]; I2 = 0%, p-value for heterogeneity = 0.54). However, there was no significant difference in the incidence of solid tumors (including malignant melanoma) (OR: 1.28 [95% CI: 0.85-1.95]) or hematologic SPMs (OR: 1.86; [95% CI: 0.81-4.27]). In conclusion, the use of anti-CD38 mAb-based combination regimens is associated with a higher risk of non-invasive cutaneous SPMs, but not solid tumors or hematologic SPMs. The increased occurrence of non-invasive cutaneous SPMs may be due to enhanced monitoring resulting from longer treatment duration with anti-CD38 mAbs.

Impact of autologous transplantation on survival in patients with newly diagnosed multiple myeloma who have high-risk cytogenetics: A meta-analysis of randomized controlled trials.

BACKGROUND: Despite routine evaluation of cytogenetics in myeloma, little is known regarding the impact of high-dose therapy (HDT) consolidation on overall survival (OS) or progression-free survival (PFS) in patients who have high-risk cytogenetics. The authors performed a meta-analysis of randomized controlled trials (RCTs) to assess the heterogeneity of HDT efficacy according to cytogenetic risk. METHODS: All RCTs in patients who had newly diagnosed myeloma from 2000 to 2021 that compared upfront HDT versus standard-dose therapy (SDT) consolidation were included. The primary objective was to assess the difference in HDT efficacy between standard-risk and high-risk cytogenetics in terms of the OS or PFS log(hazard ratio) (HR). The pooled OS and PFS HR was calculated according to cytogenetic-risk subgroup using a random-effects model, and heterogeneity (I2 ) (the percentage of total observed variability explained by between-study differences) was assessed using an interaction test. RESULTS: After screening 3307 citations, 6 RCTs were included for PFS analysis, and 4 were included for OS analysis. The median follow-up ranged from 3.1 to 7.8 years. The pooled OS HR for HDT versus SDT consolidation in patients with standard-risk and high-risk cytogenetics was 0.90 (95% confidence interval [CI], 0.70-1.17; I2 = 0%) and 0.66 (95% CI, 0.45-0.97; I2 = 0%), respectively. The difference in HDT efficacy in terms of OS between standard-risk and high-risk patients was statistically significant in favor of the high-risk group (P for interaction = .03). The pooled PFS HR for HDT versus SDT was 0.65 (95% CI 0.56-0.76; I2 = 0%) versus 0.52 (95% CI, 0.33-0.83; I2 = 55%), respectively. The difference in HDT efficacy in terms of PFS between standard-risk and high-risk patients was not significant (P for interaction = .25). CONCLUSIONS: The magnitude of OS benefit with upfront HDT is cytogenetics-dependent. Patients with high-risk cytogenetics should preferably receive upfront rather than delayed HDT consolidation. LAY SUMMARY: Upfront autologous stem cell transplantation improves overall survival in patients with newly diagnosed myeloma harboring high-risk cytogenetics.

Checkpoint Inhibitors in Multiple Myeloma: Intriguing Potential and Unfulfilled Promises.

Immune dysregulation and alteration of the bone marrow microenvironment allowing plasma cells to escape immune surveillance are well-known factors associated with the proliferation of clonal plasma cells and development of multiple myeloma (MM). Whilst immunotherapeutic approaches are now commonplace in a wide spectrum of malignancies, this aberration of myeloma development gives rise to the biological rationale for the use of immune checkpoint inhibitors (ICIs) in MM. However, the initial experience with these agents has been challenging with limited single agent efficacy, significant toxicity, and side effects. Herein, we review the biological and immunological aspects of MM and ICIs. We discuss the basic biology of immune checkpoint inhibitors, mechanisms of resistance, and drug failure patterns, review the published clinical trial data for ICIs in MM, and look towards the future of ICIs for MM treatment.

The Human Microbiota in Multiple Myeloma and Proteasome Inhibitors.

The gut microbiota plays a significant role in health and disease, including cancer development and treatment. The importance of the gut microbiota in the efficacy and toxicity of novel therapies and immunotherapy is increasingly recognized. Plasma cells in multiple myeloma have the potential to survive in the gastrointestinal tract for long periods of time. The nature of the gut microbiota impacts the degree of antigen stimulation of these cells and may play a role in mutation development and clonal evolution. Furthermore, myeloma therapies such as proteasome inhibitors and alkylating agents, commonly used to treat patients, are frequently associated with gastrointestinal adverse events. Herein we review the gut microbiota and its role in hematopoiesis, pathogenesis of myeloma, and efficacy/toxicity of anti-myeloma therapies.

Comparison of different techniques to identify cardiac involvement in immunoglobulin light chain (AL) amyloidosis.

We retrospectively reviewed the utility of N-terminal prohormone of brain natriuretic peptide (NT-proBNP) and transthoracic echocardiogram (TTE) in diagnosing cardiac involvement in patients with biopsy-proven systemic immunoglobulin light chain amyloidosis seen at the Mayo Clinic between 1 January 2006 and 30 December 2015. We analyzed 2 cohorts: patients undergoing endomyocardial biopsy for suspicion of cardiac involvement (cohort 1) and patients who had serum NT-proBNP and comprehensive echocardiographic evaluation at diagnosis (cohort 2). Of 179 patients undergoing endomyocardial biopsy (cohort 1), 173 (97%) had evidence of amyloid deposition, with 159 having NT-proBNP performed at the time of the procedure. The NT-proBNP was elevated (>300 pg/mL) in all 159 patients (sensitivity, 100%; median NT-proBNP, 4917 pg/mL; range, 355-69 541). The left ventricular ejection fraction, interventricular septal thickness, and strain rate were abnormal in 89/168 (53%), 102/64 (61%) and 92/95 (97%), respectively. Among cohort 2 (n = 342), 259 (76%) had an elevated NT-proBNP, of whom 237 (92%) had an abnormality detected on TTE. Of 83 patients with normal NT-proBNP <300 pg/mL, 27 (33%) had an abnormality on TTE (all with borderline strain rate -18% to -15%). Only 5/27 patients were considered to have possible early cardiac involvement and none had any other diagnostic or classical features of amyloidosis on TTE. The combination of NT-proBNP and comprehensive echocardiographic evaluation can diagnose cardiac amyloidosis negating the need for endomyocardial biopsy. A negative NT-proBNP rules out clinically meaningful cardiac involvement and may obviate the routine use of TTE in patients with a low clinical suspicion of cardiac amyloidosis.

Plasma cell proliferative index post-transplant is a powerful predictor of prognosis in myeloma patients failing to achieve a complete response.

Myeloma patients failing to achieve a complete response post autologous stem cell transplantation are heterogeneous, some ultimately achieving deeper responses and prolonged remission, whilst others relapse rapidly with poor outcomes. We evaluated the prognostic impact of the plasma cell proliferative index (PCPI) post-therapy, in 382 patients with myeloma failing to achieve complete response at 100 days post-transplant. Sixty percent (n = 230) of patients had zero clonal or too few clonal plasma cells to accurately assess PCPI (No PCPI). The remaining 40% (n = 152) of patients had PCPI performed with 79% (n = 120) having a low PCPI and 21% (n = 32) having an elevated PCPI. Patients with an elevated PCPI had significantly shorter progression free and overall survival. The median PFS was 8 months for elevated PCPI vs. 19 months for low PCPI vs. 24 months for no PCPI (p < 0.0001). The median OS was 27 months for elevated PCPI vs. 79 months for low PCPI vs. not reached for no PCPI, p < 0.0001). On multivariable analysis post-therapy PCPI was an independent predictor of progression free and overall survival. The PCPI post-therapy is a powerful predictor of survival and risk stratifies myeloma patients failing to achieve complete response early in the disease course.

Safety and efficacy of propylene glycol-free melphalan as conditioning in patients with AL amyloidosis undergoing stem cell transplantation.

High-dose melphalan is the standard conditioning regimen for patients with AL amyloidosis receiving autologous stem cell transplantation. Conventional formulations require propylene glycol (PG) as a co-solvent and melphalan has limited solubility and chemical stability after reconstitution, with potential risks for propylene glycol-related complications. Captisol-stabilized propylene glycol-free (PG-free) melphalan has been developed with improved solubility and chemical stability. We compared a cohort of patients with AL amyloidosis receiving PG melphalan (n = 96) to those receiving PG-free melphalan (n = 48) as conditioning for autologous stem cell transplantation. Median time to neutrophil and platelet engraftment was the same; 14 days PG melphalan vs 14 days PG-free melphalan, p = 0.73 and 16 days PG melphalan vs 16 days PG-free melphalan, p = 0.52, respectively. Hospitalization rate was similar in both cohorts, 68% PG melphalan vs 58% PG-free melphalan, p = 0.27. All-cause mortality at 100 days was not statistically significant, 3% PG melphalan vs 2% PG-free melphalan, p > 0.99. Overall response rate (ORR) and rates of complete response (CR) were similar (ORR 93% PG melphalan vs 94% PG-free melphalan, p > 0.99 and CR 39% PG melphalan vs 32% PG-free melphalan, p = 0.46). PG-free melphalan showed a comparable safety and efficacy profile to PG melphalan in patients with AL amyloidosis receiving stem cell transplantation.

Plasma cell proliferative index is an independent predictor of progression in smoldering multiple myeloma.

The plasma cell proliferative index (PCPI), determined by a slide technique or by flow cytometry, detects cells in the S phase of the cell cycle and is a useful prognostic tool in patients with plasma cell disorders such as multiple myeloma and amyloidosis. We conducted a retrospective review analyzing the prognostic effect of PCPI in 306 patients with smoldering multiple myeloma (SMM). Seventy-nine (26%) patients had an elevated PCPI (>0.5). An elevated PCPI predicted an inferior time to progression (median, 3.0 vs 7.1 years for those with a low PCPI; P = .0004). Within 24 months, the progression rate was significantly higher for patients with an elevated PCPI (49% vs. 20%; P < .0001). PCPI is a valuable tool in risk stratifying patients with SMM and identifies patients with earlier progression who may benefit from closer follow-up and consideration of early intervention trials.

Bortezomib, lenalidomide, and dexamethasone (VRd) followed by autologous stem cell transplant for multiple myeloma.

We retrospectively reviewed all patients (n = 243) receiving bortezomib, lenalidomide, and dexamethasone (VRd) induction followed by autologous stem cell transplantation (ASCT) for multiple myeloma at the Mayo Clinic between January 2010 and April of 2017. Median age was 61 (interquartile range, 55-67) with 62% of patients being male. High-risk cytogenetic abnormalities (HRA) were present in 34% of patients. A total of 166 (68%) patients received some form of maintenance/other therapy post transplant (no maintenance (NM, n = 77), lenalidomide maintenance (LM, n = 108), bortezomib maintenance (BM, n = 39), and other therapy (OT, n = 19)). Overall response rate at day 100 post ASCT was 99% (CR 42%) with CR rate increasing to 62% at time of best response post transplant. Two year and 5 year overall survival rates were 90% and 67%, respectively, with an estimated median overall survival (OS) and progression-free survival (PFS) of 96 and 28 months, respectively. HRA was associated with a worse OS but not PFS (median OS: not reached for standard risk vs 60 months for HRA, P = 0.0006; median PFS: 27 months for standard risk vs 22 months for HRA, P = 0.70). The combination of VRd followed by ASCT is a highly effective regimen producing deep and durable responses in many patients.

Therapy for relapsed multiple myeloma.

Despite significant progress in our understanding and the development of novel therapies, most patients with multiple myeloma will experience relapse of their disease. Therapy of relapsed myeloma has improved due to the availability of novel agents that are highly active against the disease. However, the selection of therapy can be challenging due to the emergence of toxicities, comorbidities and frailty. In the following we discuss our approach to the treatment of the patient with relapsed myeloma.

Utility and prognostic value of 18 F-FDG positron emission tomography-computed tomography scans in patients with newly diagnosed multiple myeloma.

Positron emission tomography-computed tomography (PET-CT) can identify bony lesions, assess disease burden, and detect extramedullary disease (EMD) in patients with multiple myeloma. We retrospectively reviewed records of patients who underwent PET-CT within 60 days of a new diagnosis (before therapy commenced) to identify the nature and prognostic impact of PET-CT abnormalities. Patients (N = 313) were seen from April 2005 through June 2017. Of the 234 patients (75%) with focal lesions (FLs), 182 (58%) had at least 3 FLs, 38 (12%) had EMD, and 204 (65%) had documented myelomatous lytic lesions. The median maximum standardized uptake value (SUVmax ) for the entire cohort was 5.9 (range 1.5-48.3). Presence of at least 3 FLs and EMD predicted inferior overall survival (OS); median OS was 57.8 months for patients with 3 or more FLs and 103.6 months for patients with fewer than 3 FLs (P = .003). The median OS was 45.5 and 71.8 months for patients with and without EMD, respectively (P = .004). No clear SUVmax cutoff was predictive of progression-free survival or OS. PET-CT is a valuable tool for assessing disease burden and could provide prognostic information about a contemporary cohort of patients with newly diagnosed myeloma who received treatment with novel agents.

Prognostic Significance of Stringent Complete Response after Stem Cell Transplantation in Immunoglobulin Light Chain Amyloidosis.

Hematologic response has emerged as a powerful prognostic factor for survival in patients with immunoglobulin light chain (AL) amyloidosis. Patients achieving a complete response (CR), based on serum and urine analysis, survive longest. However, data regarding the impact of bone marrow features post-therapy on response and survival are limited. We evaluated the impact of achieving a stringent CR (sCR), defined as undetectable bone marrow clonal plasma cells by flow cytometry, in patients with AL amyloidosis receiving an autologous stem cell transplant. A total of 573 consecutive patients transplanted for AL amyloidosis at the Mayo Clinic between April 2002 and August 2016 were included in the analysis. Of 540 patients in whom response was assessable, 220 patients (41%) achieved a CR, of whom 212 (96%) had a bone marrow biopsy at time of response assessment and were further analyzed for determination of sCR; 166 patients (78%) with a CR achieved an sCR, representing 31% of the whole cohort. Patients achieving a CR had a higher median percentage of bone marrow plasma cells (10% for CR versus 6% for sCR, P = .03), more patients with bone marrow plasma cells ≥ 10% (50% for CR versus 33% for sCR, P = .04), and were less likely to receive chemotherapy before transplantation (30% for CR versus 49% for sCR, P = .03) compared with those achieving sCR. Median overall survival for all patients achieving a CR was 175 months and was not statistically different between those achieving an sCR compared with those achieving a CR only (median not reached for sCR versus 175 months for CR, P = .65). Progression-free survival, however, was significantly shorter in patients failing to achieve an sCR (151 months for sCR versus 72 months for CR, P = .0003). Bone marrow examination post-transplant in AL amyloidosis is important and identifies patients who fail to achieve an sCR and progress earlier.

Autologous Stem Cell Transplant for Immunoglobulin Light Chain Amyloidosis Patients Aged 70 to 75.

Autologous stem cell transplantation (ASCT) has been used in treatment for immunoglobulin light chain (AL) amyloidosis for over 2 decades and is generally reserved for patients younger than 70 years. Herein we report on outcomes of ASCT in a cohort of patients with AL amyloidosis aged 70 years or older. Between August of 2002 and April of 2017, 34 patients aged 70 years or older, with biopsy-proven AL amyloidosis, received an ASCT at the Mayo Clinic Rochester. Seventy percent of patients (n = 24) were transplanted within 6 months of diagnosis, and 74% (n = 25) received reduced-intensity conditioning with melphalan <200 mg/m2. Sixty-five percent of patients (n = 22) required hospitalization with a median duration of hospital admission of 8 days. Common reasons for hospitalization included fever or infection (14%), cardiac arrhythmia (14%), nutritional support (24%), and volume overload (19%). Overall response rate was 75%, with a complete response seen in 25% of patients. Overall survival and progression-free survival for the cohort were 66 months and 40 months, respectively. One patient died within 100 days of transplant, representing a 3% 100-day mortality rate. ASCT is safe and efficacious in carefully screened patients aged 70 or above.

Light chain type predicts organ involvement and survival in AL amyloidosis patients receiving stem cell transplantation.

We evaluated the impact of light chain type, lambda (λ) or kappa (κ), on disease features and outcomes in patients with immunoglobulin light chain (AL) amyloidosis receiving stem cell transplant at the Mayo Clinic between October 2002 and August 2016. Patients with λ AL amyloidosis had higher rates of renal and neurological involvement (λ 69% vs κ 57%, P = .02 and λ 16% vs κ 9%, P = .03, respectively). Patients with κ AL amyloidosis had more hepatic involvement (λ 7% vs κ 18%, P = .0003). Complete response rate was 43% for both groups and overall response rates were similar (λ 85% vs κ 91%, P = .12). Patients with κ light chain amyloidosis had better progression-free and overall survival (PFS: λ 74 months vs κ 101 months, P = .0064 and OS: λ 121 months vs κ not reached, P = .003). Mayo stage 2004 was more predictive of survival in the λ cohort (median OS of 143 months stage I vs 77 months stage II vs 33 months stage III, P < .0001) than in the κ cohort (median OS not reached for stage I and II and 102 months for stage III, P = .044). Conditioning dose predicted survival in the λ cohort only (median OS 149 months for melphalan 200 mg/m2 vs 50 months for melphalan <200 mg/m2, P < .0001; median OS κ not reached for melphalan 200 mg/m2 or <200 mg/m2, P = .38). On multivariate analysis, light chain type remained an independent predictor of survival. Light chain type predicts organ involvement and survival in patients with AL amyloidosis receiving stem cell transplant.

Plasma cell proliferative index predicts outcome in immunoglobulin light chain amyloidosis treated with stem cell transplantation.

The plasma cell proliferative index provides an insight into plasma cell biology in plasma cell disorders and is an important prognostic marker in myeloma and smoldering myeloma. We analyzed the prognostic impact of the plasma cell proliferative index in 513 patients with systemic immunoglobulin light chain (AL) amyloidosis undergoing stem cell transplantation at the Mayo Clinic between 1st January 2003 and 31st August 2016. Two cohorts were identified according to Low or Elevated plasma cell proliferative index. Patients with an Elevated plasma cell proliferative index had more cardiac involvement (56% vs 44%; P=0.01), less renal involvement (55% vs 70%; P=0.001), and were more likely to have 10% or over bone marrow plasma cells (58% vs 32%; P<0.0001) compared to those with a Low plasma cell proliferative index. Both progression-free survival and overall survival were lower in patients with an Elevated compared to Low plasma cell proliferative index: median progression-free survival 44 vs 95 months (P<0.0001) and median overall survival 102 vs 143 months (P=0.0003). All-cause mortality at 100 days was higher in patients with an Elevated plasma cell proliferative index (elevated 10.3% vs low 4.3%; P=0.008). On multivariate analysis Elevated plasma cell proliferative index was an independent prognostic factor for overall survival (Hazard Ratio 1.5, 95%CI: 1.1-2.1; P=0.021). The plasma cell proliferative index is an important prognostic tool in patients with AL amyloidosis undergoing stem cell transplant.

Stem Cell Transplantation for Light Chain Amyloidosis: Decreased Early Mortality Over Time.

Purpose Autologous stem-cell transplantation (ASCT) has been used in patients with immunoglobulin light chain (AL) amyloidosis for more than two decades. Early experience raised concerns regarding safety with high early-mortality rates. Patients and Methods We report 20 years of experience with ASCT for AL amyloidosis at the Mayo Clinic Rochester. In all, 672 consecutive patients receiving ASCT for AL amyloidosis were divided into three cohorts on the basis of date of transplantation (cohort 1, 1996-2002 [n = 124]; cohort 2, 2003-2009 [n = 302]; and cohort 3, 2010-2016 [n = 246]). Results The median age for the entire cohort was 59 years, with patients in cohort 3 being slightly older than those in the other two cohorts (60 v 58 v 54 years for cohorts 3, 2, and 1, respectively; P < .001). Fewer patients in cohort 3 had more than two organs involved (9% v 18% v 19% for cohorts 3, 2, and 1, respectively; P < .001). More patients received pretransplantation therapy in cohort 3 compared with earlier time periods (49% v 38% v 42% for cohorts 3, 2, and 1, respectively; P = .02). Hematologic response was higher in cohort 3 (84% v 79% v 69% for cohorts 3, 2, and 1, respectively; P = .002). Median overall survival for the entire cohort was 122 months and improved over time (not reached v 120 months v 75 months for cohorts 3, 2, and 1, respectively; P < .001). Treatment-related mortality declined over time (2.4% v 8.6% v 14.5% for cohorts 3, 2, and 1, respectively; P < .001). On multivariable analysis, conditioning dose, Mayo stage 2012, and hematologic response were independent predictors of survival. Conclusion ASCT is a highly effective therapy for AL amyloidosis. The improved survival and markedly reduced treatment-related mortality in eligible patients indicate that this will remain an important first-line option even in the era of treatment approaches that use novel agents.

Association of dose escalation of octreotide long-acting release on clinical symptoms and tumor markers and response among patients with neuroendocrine tumors.

Patients with nonresectable metastatic neuroendocrine tumors (NETs) experience symptoms of hormone hypersecretion including diarrhea, flushing, and bronchoconstriction, which can interfere with quality of life [Anthony and Vinik (2011) Pancreas, 40:987]. Treatment with a long-acting release formulation of octreotide, a somatostatin analog, can help to alleviate these symptoms. Although high doses of octreotide are often required for adequate symptom control, the relationship between octreotide dose escalation and symptom control in the NET context is not well quantified in the literature. A retrospective chart review was conducted of nonresectable metastatic NET patients who received a dose greater than 30 mg intramuscular octreotide long-acting formulation (O-LAR) at any time between January 2005 and December 2011 at the British Columbia Cancer Agency (BCCA). The association between dose escalation of O-LAR, chromogranin A (CGA), 24-h urine 5-hydoxyindoacetate (5-HIAA), symptom control, and radiological progression was explored. Dose escalation of O-LAR was associated with improved symptom control in NET patients who were refractory to the standard dose levels. Reduction of serum CGA & 5-HIAA levels by at least 10% was observed in 31% and 23% respectively. Retrospective review of imaging did not document any reductions in tumor volume. Higher doses of O-LAR are associated with improved symptom control in NET patients. The variability in tumor marker levels in response to O-LAR dose escalation may indicate that tumor marker levels may not be an accurate assessment of therapeutic efficacy.