Outcomes of patients with multiple myeloma refractory to standard dose vs low dose lenalidomide.

Refractoriness to lenalidomide is an important factor determining the choice of therapy at first relapse in multiple myeloma (MM). It remains debatable if resistance to lenalidomide varies among MM refractory to standard doses vs low dose maintenance doses. In this study, we assessed the outcomes with subsequent therapies in patients with MM refractory to standard dose vs low dose lenalidomide. We retrospectively reviewed all patients with MM at our institution who received first line therapy with lenalidomide containing regimens, and assessed progression free survival (PFS) and overall survival for these patients for second line therapy, and with lenalidomide retreatment. For second line therapy, we found no difference in the PFS between standard dose refractory and low dose refractory groups (median PFS 14 months vs 14 months, p = 0.95), while the PFS for both these groups was inferior to the not refractory group (median PFS 30 months, p < 0.001 for both pairs). Similar trends were seen among these groups on lenalidomide retreatment, and on multivariable analysis. These data suggest that refractoriness to lenalidomide is not dose dependent, and definition of lenalidomide refractoriness should not depend on the dose of lenalidomide to which the disease was considered refractory.

Efficacy and safety of daratumumab, pomalidomide, and dexamethasone versus daratumumab, carfilzomib, and dexamethasone in daratumumab-naïve relapsed multiple myeloma.

OBJECTIVES AND METHODS: We conducted a multicenter retrospective study to analyze the safety and efficacy of DPd versus DKd in daratumumab naïve RRMM patients treated in real-world practice. RESULTS: A total of 187 patients with RRMM were included in the analysis; 128 patients received DPd, and 59 patients received DKd. A vast majority (80%) of patients had lenalidomide refractory disease and nearly 50% had bortezomib refractory disease. The overall response and complete response rates were 76% and 34% in the DPd group versus 80% and 51% in the DKd group, respectively. With a median follow up of 36 months for the entire patient population, median PFS and OS in the DPd versus DKd groups were 12, 12, 37, and 35 months, respectively. The most common grade 3+ adverse events in the DPd versus DKd groups were neutropenia (32% vs. 7%), anemia (14% vs. 10%), thrombocytopenia (13% vs. 15%), and cardiovascular events (4% vs. 15%), respectively. Both DPd and DKd appeared to be a safe and effective treatment options for RRMM. CONCLUSIONS: While there were more cytopenias associated with DPd and more cardiovascular side effects with DKd, there were no significant differences in the survival outcomes with these two regimens.

Outcomes of patients with primary refractory multiple myeloma in the era of triplet and quadruplet induction therapy.

Patients with multiple myeloma (MM) who do not respond to initial therapy have worse outcomes than primary responders, and effective treatments are lacking in this population. However, the outcomes of primary refractory disease in the modern treatment era have not yet been studied. We reviewed patients with MM treated with triplet/quadruplet therapy at our institution to assess the incidence of primary refractory disease and the impact of salvage therapies in this population. We identified 1127 patients, of whom 1086 were evaluated for hematologic responses after 4 to 6 cycles. Of these, 93.3% (1013) had evidence of response, whereas 6.7% (73) had primary refractory disease. With a median overall survival (OS) of 51.3 months, patients with primary refractory disease had an increased risk of shorter survival in univariable and multivariable analyses (hazard ratio [HR], 3.5 [95% confidence interval (CI), 2.5-4.9]; HR, 4.3 [95% CI, 2.6-6.9], respectively). In the subgroup analysis of patients with primary refractory disease, those who received second-line autologous stem cell transplantation (ASCT) had increased second progression-free survival (20.9 vs 8.1 months; P < .01) and second OS (74.7 vs 31.3 months; P = .02) compared with patients who did not. We conclude that early progression remains a significant factor for shorter OS in the current era, and salvage ASCT could be the most beneficial option for this population.

Thrombosis in multiple myeloma: Risk estimation by induction regimen and association with overall survival.

Lenalidomide-containing (R) triplet and quadruplet regimens are the standard of care for multiple myeloma (MM) and have been shown to increase the risk of thrombosis. The association between thromboembolism (TE) and survival in the novel multidrug era is not yet delineated. In this study, we evaluated the incidence of TE during the first year of MM diagnosis, its association with the type of induction regimen, and its impact on overall survival. We studied 672 newly diagnosed MM (NDMM) patients who received a triplet or quadruplet lenalidomide-based induction at the Mayo Clinic, Rochester. TE was diagnosed in 83 patients (12.4%). Of these, 56 (8.3%) had a deep venous thrombosis (DVT), 23 (3.4%) had a pulmonary embolism (PE) with or without the DVT, and 4 (0.6%) patients had a stroke. Carfilzomib-Rd (KRd) had the highest risk of TE (21.1%, 18/85), followed by quadruplets (11.1%, 5/45), bortezomib-Rd (9.6%, 51/531), and 0/11 (0%), treated with other lenalidomide-containing regimens. The difference in TE risk between KRd and the other regimens was statistically significant (OR = 2.6, p < .01). Nine patients developed a TE before being exposed to any treatment. Survival was significantly lower among patients that developed a TE (66 vs. 133 months, p < .01). The association of TE with reduced survival demonstrated in univariate analysis (HR = 2.2, 95% CI = 1.6-3.3) was maintained in the multivariable analysis adjusted for high-risk interphase fluorescence in situ hybridization (FISH), sex, age, receipt of an upfront transplant, the response at induction, and the International Staging System (ISS) (HR = 2.61, CI = 1.74-3.9). We conclude that TE is an important aspect of MM management, and effective management is especially relevant in the novel treatment era.

Impact of the time interval between end of induction and autologous hematopoietic transplantation in newly diagnosed patients with multiple myeloma.

Multiple Myeloma patients eligible for autologous hematopoietic transplantation (AHT) typically receive 3-6 cycles of induction therapy before transplant. The last induction cycle is completed 2-4 weeks prior to mobilization. We evaluated the impact of the time interval between end of induction and AHT on progression-free survival (PFS) and overall survival (OS). A total of 1055 patients who underwent AHT were identified. The median time to transplant (TTT) was 33 days (27-42 quartile range). Patients with less than 33 days of TTT had significantly prolonged PFS (35.6 vs. 32.1 months, p < 0.03) but non-significant OS differences compared to those with more than 33 days. Quartile comparisons showed that patients in the 1st quartile (less than 27 days) had significantly prolonged PFS (36.7 vs. 30.9 months, p < 0.01) compared to the 4th quartile group (more than 42 days). In a subgroup analysis of patients with partial or worse biochemical response prior to transplant, patients in the 1st quartile had significantly prolonged PFS (37.7 vs. 28.7 months, p < 0.04) compared to the 4th quartile group. In conclusion, we showed that a prolonged TTT is associated with inferior outcomes compared to tighter chemotherapy schedules. This finding was especially prevalent in patients with partial response at induction.

An update on the safety of ixazomib for the treatment of multiple myeloma.

INTRODUCTION: Treatment options for multiple myeloma (MM) have rapidly expanded over the past few years with several newly approved drugs. While there is need to explore treatments that lead to longer responses and survival, special consideration should be given on reducing treatment burden, reducing toxicities, and improving quality of life. Ixazomib is the first oral proteasome inhibitor for the treatment of MM, combining clinical efficacy with a favorable safety profile. AREAS COVERED: Here, we discuss the clinical efficacy and safety of ixazomib. Pharmacokinetic considerations, management of common toxicities, and the impact of the drug on the current and future treatment strategies are also discussed. EXPERT OPINION: Ixazomib is an effective and welltolerated MM drug. It is also being studied in combination with other newer agents. It does not have long-term cumulative toxicities, and the most adverse events are mild and manageable. These findings, along with the ease of oral administration, make it a possible option for long-term treatment approaches for MM patients, as well as in the frail/elderly patient population.

Current approaches to management of newly diagnosed multiple myeloma.

Major developments in the treatment of multiple myeloma (MM) over the past decade have led to a continued improvement in survival. Significant progress has been made with deeper and longer remissions seen with newer treatment approaches-both for induction as well as maintenance therapy. The treatment approach to MM is guided by several factors including patient age, frailty, comorbidities, eligibility for autologous stem cell transplantation (ASCT), and risk stratification into standard-risk or high-risk MM. High-risk MM is defined by the presence of t(4;14), t(14;16), t(14;20), del (17p), TP53 mutation, or gain (1q). Transplant eligible patients should receive 4-6 cycles of induction followed by stem cell collection. Patients can then undergo ASCT, or continue induction therapy and shift to maintenance, delaying ASCT till first relapse. Transplant ineligible patients should receive induction therapy followed by maintenance. For induction therapy prior to ASCT, a proteasome inhibitor-IMiD combination remains standard with monoclonal antibody-based quadruplets preferred in high-risk patients. Among transplant ineligible patients, those with standard-risk MM should receive DRd continued until disease progression, while bortezomib containing regimens (VRd or VRd lite) can be considered for high-risk patients. Finally, standard-risk patients should receive lenalidomide maintenance after induction/ASCT, while proteasome inhibitor-IMiD combinations should be used for high-risk patients.

Utility of PET/CT in assessing early treatment response in patients with newly diagnosed multiple myeloma.

Multiple myeloma (MM) is a plasma cell malignancy that is characterized by diverse clinical presentations. Although biochemical assessment of disease activity is commonly used to monitor treatment response, findings on magnetic resonance imaging and positron emission tomography (PET)/computed tomography (CT), among other imaging modalities, have proven to harbor prognostic value. We sought to corroborate these findings by examining the prognostic significance of fluorodeoxyglucose PET/CT scanning in the setting of newly diagnosed MM. We retrospectively analyzed 195 patients with a PET/CT available at diagnosis and at 6 months posttreatment to examine their value as an adjuvant metric to conventional hematologic responses in terms of time to next treatment (TTNT) and overall survival (OS). The median TTNT and OS for the entire cohort were 24.6 months (95% confidence interval [CI], 20.4-29.1) and 79 months (95% CI, 63.1-119.1), respectively. When comparing PET/CT negative (-) with PET/CT positive (+) patients, we found significantly prolonged median TTNT (55.2 vs 17.8 months, P < .0001) and OS (unreached vs 60.8 months, P < .0001) in the former group. We then examined the additive value of PET/CT on the hematologic response achieved at 6 months and found that PET/CT (-) is associated with significantly increased median TTNT and OS for the very good partial response (VGPR) group and the less than VGPR group. Importantly, PET/CT retained prognostic significance after adjusting for multiple other predictive variables. We conclude that a PET/CT (-) at 6 months confers a significant prognostic advantage for patients with newly diagnosed MM and adds significant value to the hematologic response assessment.

A national analysis of patterns of care and outcomes for adults diagnosed with desmoplastic small round cell tumors in the United States.

BACKGROUND: Because of the rarity of desmoplastic small round cell tumors (DSRCT), there is a lack of data describing patterns of care and survival for these patients. Using a national tumor registry, the current study sought to describe patterns of care and clinical outcomes for patients with DSCRT. METHODS: Data from the National Cancer Database were used to identify 491 patients aged 18 years or older diagnosed with DSRCT between 2004 and 2014. Multivariable Cox proportional hazards regression analysis was used to identify factors associated with overall survival (OS). RESULTS: Among all patients, 41.2% (n = 200), underwent surgical resection of their primary tumor, chemotherapy was administered to 86.5% (n = 415) of patients, while radiation therapy was administered to 13.0% (n = 63) of patients. Over the study, 69.7% of patients died with a median OS of 25.9 months (interquartile range [IQR]: 22.7-27.5); 1-, 3-, and 5-year OS were 78.6%, 32.3%, and 18.4%, respectively. On multivariable analysis, stage IV disease (Hazard Ratio [HR] = 2.12, 95% CI: 1.41-3.18), receipt of surgery (HR = 0.68, 95% CI: 0.50-0.91), chemotherapy (HR = 0.52, 95% CI: 0.35-0.78), or radiation therapy (HR = 0.55, 95% CI: 0.33-0.92) were independently associated with OS. CONCLUSIONS: Although receipt of multimodality treatment may lead to improved survival, further research and clinical trials are required to establish best practices for the care of DSRCT.

Minimally Invasive Versus Open Primary Resection for Retroperitoneal Soft Tissue Sarcoma: A Propensity-Matched Study From the National Cancer Database.

BACKGROUND: Although well described for gastrointestinal and pelvic cancers, use of minimally invasive surgery (MIS) for the management of retroperitoneal soft tissue sarcoma (RPS) remains unknown. The current study aimed to describe patterns of MIS use and assess the association between MIS and clinical outcomes among patients undergoing surgery for RPS. METHODS: Patients undergoing a primary resection for RPS between 2010 and 2014 were identified using the National Cancer Database. Multivariable logistic and Cox proportional hazards models were used to assess the association between use of MIS and clinical outcomes. Sensitivity analysis was performed using propensity score-matching (PSM). RESULTS: This study identified 3844 patients who met the inclusion criteria. Of these patients, 89.3% (n = 3432) underwent an open surgery, whereas 10.7% (n = 412) underwent MIS. The patients undergoing MIS were more likely to present with smaller tumors (open vs MIS: median tumor size, 17 cm; interquartile range [IQR, 9.8-26.0] vs 10.5 cm [IQR, 6.5-18.0]) and to undergo surgery at community hospitals (26.8% vs 36.1%; both P < 0.001). Although MIS was associated with a shorter hospital length of stay [LOS] (median LOS, 6 days [IQR, 5-9 days] vs 4 days [IQR, 2-7]; P < 0.001), postoperative mortality and overall survival were comparable between the two treatment groups (all P > 0.05). These findings were confirmed using PSM. CONCLUSIONS: MIS was associated with a shorter LOS, however, postoperative mortality and overall survival were comparable by operative approach. Future research is required to evaluate the use of MIS for the management of RPS. Policies are required to ensure that patients receive care in accordance with best practices and recommended guidelines.