Outcomes with allogeneic stem cell transplant using cryopreserved versus fresh hematopoietic progenitor cell products.

BACKGROUND: Allogeneic hematopoietic stem cell transplant (alloHSCT) is a mainstay of treatment for hematologic malignancies such as acute leukemias and aggressive lymphomas. Historically, fresh hematopoietic progenitor cell (HPC) products have been preferred to cryopreserved products (cryo-HPC) due to concerns of loss of stem cell viability and number with the cryopreservation procedure. OBJECTIVE: We aimed to analyze the outcomes of patients who received cryo-HPCs during the COVID-19 pandemic and compare this against historical cohorts that received fresh HPC. STUDY DESIGN: A retrospective chart review was conducted on all adult patients who received a peripheral blood alloHSCT in British Columbia, Canada between June 2017 and November 2021. Baseline characteristics, Kaplan-Meier (KM) overall survival (OS), engraftment, and incidences of acute and chronic graft versus host disease were compared between patients who received cryo-HPCs and fresh HPCs. Univariable analysis followed by multivariable analysis was performed using a backward stepwise selection procedure to generate predictors of OS, cumulative incidence of relapse (CIR), nonrelapse mortality (NRM), and primary and secondary graft failure. RESULTS: Three hundred eighty-three patients were included in the analysis, with cryo-HPC representing 40%. Median viability was higher in the fresh-HPC group at 99.2% (IQR 98.3-99.5) versus cryo-HPCs at 97.0% (96.0, 98.6) (P < 0.01). The 12-month actuarial survivals were 77% in the fresh HPC and 75% in the cryo-HPC groups (P = 0.21). There were no differences between cryo-HPCs and fresh HPCs on univariable analysis of OS, CIR, or NRM. There was a shorter median time to platelet engraftment in patients receiving fresh HPC at 17 days (IQR 16, 20) versus cryo-HPC at 21 days (IQR 18, 29), P < 0.001. There was a shorter median time to neutrophil engraftment in the fresh HPC group at 17 days (IQR 14, 20) versus 20 days (17, 23), P < 0.001. Cryo-HPC accounted for 5 out of 6 cases of primary graft failure (P = 0.04), and 3 out of five cases of secondary graft failure (P = 0.39). There were no significant differences in acute GVHD between the fresh HPC and cryo-HPC groups (P = 0.34). The incidence of moderate or severe chronic GVHD was 32% in the fresh-HPC group and 17% in the cryo-HPC group (P < 0.001). In multivariable analysis, cryopreservation did not emerge as an independent predictor of OS, CIR, NRM, primary GF or secondary GF. However, viability <90% on arrival at our center was a significant predictor of OS (HR 5.3, 2.3-12.3, P < 0.01), primary graft failure (OR 36.3, 5.4-210.2, P < 0.01), and secondary graft failure (OR 18.4, 1.7-121.1, P < 0.01). CONCLUSIONS: Patients who received cryo-HPCs had similar OS and relapse rates to those who received fresh-HPCs but typically took 2-3 days longer to achieve engraftment of platelets or neutrophils and were associated increased primary graft failure. However, after accounting for multiple variables, cryopreservation was no longer a significant predictor of survival or engraftment while viability <90% emerged as an important predictor of OS, primary graft failure, and secondary graft failure. If confirmed, this suggests that viability on arrival at the infusion center may be a good quality control indicator used to identify HPC products that may warrant recollection if the risk of graft failure is sufficiently increased.

Outcomes of Hodgkin variant Richter transformation in chronic lymphocytic leukaemia and small lymphocytic lymphoma in British Columbia.

Hodgkin variant Richter transformation (HvRT) is a rare and challenging complication of chronic lymphocytic leukaemia (CLL) for which information on prognostic factors and treatment approaches remain limited. We analysed characteristics and survival outcomes of a population-based cohort of 32 patients with HvRT identified in British Columbia over a 40-year period. Median interval from CLL diagnosis to HvRT was 5.6 years (range, 0-33.6), with five cases diagnosed concurrently. Most patients (80%) had treatment for CLL prior to HvRT. Median age at HvRT was 71 years (range, 51-86) and the majority of patients had high-risk disease, including stage 3-4 in 87% and International Prognostic Score (IPS) ≥ 4 in 65%. Two-year progression-free (PFS) and overall survival (OS) from HvRT were 47% (95% CI: 29%-64%) and 57% (95% CI: 38%-72%), respectively. OS from HvRT was significantly worse in those with anaemia (p = 0.02), elevated lactate dehydrogenase (p = 0.04), high IPS (p = 0.04), and worse performance status (p = 0.001). For those treated with curative-intent ABVD/ABVD-like therapy, 2-year PFS and OS were 70% (95% CI: 45%-85%) and 74% (95% CI: 49%-89%), respectively. In this real-world population-based cohort, HvRT was associated with poor clinical outcomes overall; however, those able to tolerate curative-intent therapy had similar survival to older patients with de novo HL.

Incidence and socioeconomic factors in older adults with acute myeloid leukaemia: Real-world outcomes from a population-based cohort.

OBJECTIVES: Acute myeloid leukaemia (AML) is a disease of older adults, who are vulnerable to socio-economic factors. We determined AML incidence in older adults and the impact of socio-economic factors on outcomes. METHODS: We included 3024 AML patients (1996-2016) identified from a population-based registry. RESULTS: AML incidence in patients ≥60 years increased from 11.01 (2001-2005) to 12.76 (2011-2016) per 100 000 population. Among 879 patients ≥60 years in recent eras (2010-2016), rural residents (<100 000 population) were less likely to be assessed by a leukaemia specialist (39% rural, 47% urban, p = .032); no difference was seen for lower (43%, quintile 1-3) vs. higher (47%, quintile 4-5) incomes (p = .235). Similar numbers received induction chemotherapy between residence (16% rural, 18% urban, p = .578) and incomes (17% lower, 17% high, p = 1.0). Differences between incomes were seen for hypomethylating agent treatment (14% low, 20% high, p = .041); this was not seen for residence (13% rural, 18% urban, p = .092). Among non-adverse karyotype patients ≥70 years, 2-year overall survival was worse for rural (5% rural, 12% urban, p = .006) and lower income (6% low, 15% high, p = .017) patients. CONCLUSIONS: AML incidence in older adults is increasing, and outcomes are worse for older rural and low-income residents; these patients face treatment barriers.

Excellent real-world outcomes of adults with Burkitt lymphoma treated with CODOX-M/IVAC plus or minus rituximab.

Treatment of Burkitt lymphoma (BL) with intensive, multi-agent chemotherapy with aggressive central nervous system (CNS) prophylaxis results in high cure rates, although no regimen is standard of care. We examined population-based survival outcomes of adults with BL treated with a modified combination of cyclophosphamide, vincristine, doxorubicin, prednisone and systemic high-dose methotrexate (MTX) (CODOX-M) with IVAC (ifosfamide, mesna, etoposide, cytarabine and intrathecal MTX) (CODOX-M/IVAC) ± rituximab over a 15-year period in British Columbia. For the 81 patients identified (including 8 with CNS involvement and 18 with human immunodeficiency virus-associated BL), 5-year progression-free survival (PFS) and overall survival (OS) were 75% [95% confidence interval (CI): 63-83%] and 77% (95% CI: 66-85%), respectively, with no treatment-related deaths. Those who completed the regimen per protocol (n = 38) had significantly improved 5-year PFS 86% (P = 0·04) and OS 92% (P = 0·008), as did those under 60 years with 5-year PFS 82% (P = 0·005) and OS 86% (P = 0·002), which remained significant in multivariate analysis [PFS: hazard ratio (HR) 3·36, P = 0·018; OS HR 4·03, P = 0·012]. Incorporation of high-dose systemic methotrexate also significantly affected multivariate survival outcomes (OS HR 0·28, P = 0·025). Stem cell transplant in first remission had no effect on OS or PFS. This large, real-world analysis of BL patients treated with CODOX-M/IVAC ± rituximab demonstrates excellent survival outcomes comparable to clinical trials. These results help to serve as a benchmark when comparing curative therapies for BL patients as novel regimens are incorporated into clinical practice.

Heterogeneity of chronic graft-versus-host disease biomarkers: association with CXCL10 and CXCR3+ NK cells.

Chronic graft-versus-host disease (cGVHD) remains one of the most significant long-term complications after allogeneic blood and marrow transplantation. Diagnostic biomarkers for cGVHD are needed for early diagnosis and may guide identification of prognostic markers. No cGVHD biomarker has yet been validated for use in clinical practice. We evaluated both previously known markers and performed discovery-based analysis for cGVHD biomarkers in a 2 independent test sets (total of 36 cases ≤1 month from diagnosis and 31 time-matched controls with no cGVHD). On the basis of these results, 11 markers were selected and evaluated in 2 independent replication cohorts (total of 134 cGVHD cases and 154 controls). cGVHD cases and controls were evaluated for several clinical covariates, and their impact on biomarkers was identified by univariate analysis. The 2 replications sets were relatively disparate in the biomarkers they replicated. Only sBAFF and, most consistently, CXCL10 were identified as significant in both replication sets. Other markers identified as significant in only 1 replication set included intercellular adhesion molecule 1 (ICAM-1), anti-LG3, aminopeptidase N, CXCL9, endothelin-1, and gelsolin. Multivariate analysis found that all covariates evaluated affected interpretation of the biomarkers. CXCL10 had an increased significance in combination with anti-LG3 and CXCL9, or inversely with CXCR3(+)CD56(bright) natural killer (NK) cells. There was significant heterogeneity of cGVHD biomarkers in a large comprehensive evaluation of cGVHD biomarkers impacted by several covariates. Only CXCL10 strongly correlated in both replication sets. Future analyses for plasma cGVHD biomarkers will need to be performed on very large patient groups with consideration of multiple covariates.

Influence of clone and deletion size on outcome in chronic lymphocytic leukemia patients with an isolated deletion 13q in a population-based analysis in British Columbia, Canada.

Deletion of the long arm of chromosome 13 (del(13q)) as the sole abnormality in chronic lymphocytic leukemia (CLL) portends a good prognosis; however, there is great outcome heterogeneity within this subgroup. The percentage of cells with a del(13q) (clone size) and the extent of the deletion are two factors that may affect outcome in CLL patients with isolated del(13q). We analyzed 248 CLL patients from the BC Provincial CLL database identified as having isolated del(13q) detected pretreatment by interphase fluorescence in situ hybridization to determine what impact clone and deletion size had on overall survival (OS) and treatment free survival (TFS). Patients with 60% or more of nuclei with a del(13q) had shorter TFS and shorter OS. A large deletion, encompassing the RB1 gene locus, was detected in half of the 90 cases with available specimens for testing, and there was no significant difference in OS and TFS between RB1-deleted and RB1-not-deleted cases. Further study in a larger sample size is required to determine the clinical interest of RB1 locus testing; however, clone size of del(13q) does predict TFS and OS and may better refine prognosis in this clinically heterogeneous population.

Allogeneic Hematopoietic Stem Cell Transplantation Is an Effective Salvage Therapy for Patients with Chronic Myeloid Leukemia Presenting with Advanced Disease or Failing Treatment with Tyrosine Kinase Inhibitors.

Allogeneic hematopoietic stem cell transplantation (HSCT) remains the only known curative therapy for chronic myeloid leukemia (CML); however, it is rarely utilized given the excellent long-term results with tyrosine kinase inhibitor (TKI) treatment. The purpose of this study is to examine HSCT outcomes for patients with CML who failed TKI therapy or presented in advanced phase and to identify predictors of survival, relapse, and nonrelapse mortality (NRM). Fifty-one patients with CML underwent HSCT for advanced disease at diagnosis (n = 15), TKI resistance as defined by the European LeukemiaNet guidelines (n = 30), TKI intolerance (n = 2), or physician preference (n = 4). At a median follow-up of 71.9 months, the 8-year overall survival (OS), event-free survival (EFS), relapse, and NRM were 68%, 46%, 41%, and 23%, respectively. In univariate analysis, predictors of OS included first chronic phase (CP1) disease status at HSCT (P = .0005), European Society for Blood and Marrow Transplantation score 1 to 4 (P = .04), and complete molecular response (CMR) to HSCT (P < .0001). Donor (female) to patient (male) gender combination (P = .02) and CMR to HSCT (P < .0001) predicted lower relapse. In multivariate analysis, CMR to HSCT remained an independent predictor of OS (odds ratio [OR], 43), EFS (OR, 56) and relapse (OR, 29). This report indicates that the outlook is excellent for those patients who remain in CP1 at the time of HSCT and achieve a CMR after HSCT. However, only approximately 50% of those in advanced phase at HSCT are long-term survivors. This highlights the ongoing need to try to identify patients earlier, before disease progression, who are destined to fail this treatment to optimize transplantation outcomes.

Favorable outcomes from allogeneic and autologous stem cell transplantation for patients with transformed nonfollicular indolent lymphoma.

The role of allogeneic (allo-) and autologous stem cell transplantation (auto-SCT) in the management of patients with transformed indolent nonfollicular non-Hodgkin lymphoma is unknown. This is a multicenter, retrospective cohort study of patients with biopsy-proven indolent B cell nonfollicular non-Hodgkin lymphoma and simultaneous or subsequent biopsy-proven aggressive histology transformation who were treated with allo-SCT or auto-SCT between 1996 and 2013. All patients received myeloablative conditioning regimens. Outcomes were compared with a cohort of 246 patients with transformed follicular lymphoma who also underwent allo-SCT (n = 47) or auto-SCT (n = 199) across the same institutions and time frame. Thirty-four patients were identified with the following underlying indolent histologies: 15 (44%) marginal zone lymphoma, 11 (32%) chronic lymphocytic leukemia, 6 (18%) small lymphocytic lymphoma, and 2 (6%) lymphoplasmacytic lymphoma. Patients received various anthracycline or platinum-containing chemotherapy regimens for transformation, incorporating rituximab in 25 (74%). Twelve (35%) subsequently underwent allo-SCT, whereas 33 (65%) underwent auto-SCT. The 3-year overall survival rate after transplantation was 67% (allo-SCT 54%, auto-SCT 74%), and 3-year progression-free survival rate was 49% (allo-SCT 40%, auto-SCT 54%). The 3-year nonrelapse mortality rate was 14% (allo-SCT 15%, auto-SCT 7%). Transplant-related mortality at 100 days was 17% for allo-SCT and 0% for auto-SCT. Adjusted for type of stem cell transplantation, 3-year overall survival, progression-free survival, and nonrelapse mortality rates were similar to those of patients with transformed follicular lymphoma receiving allo-SCT and auto-SCT (P = .38, P = .69, and P = .54, respectively). Allo-SCT and auto-SCT may be reasonable treatments for selected patients with transformed nonfollicular indolent lymphoma, although medium-term outcomes and toxicity appear to be more favorable with auto-SCT.

Population-level impact of ibrutinib for chronic lymphocytic leukemia in British Columbia, Canada.

Ibrutinib has dramatically changed the treatment landscape for chronic lymphocytic leukemia (CLL) since its availability in British Columbia (BC), Canada in 2014. We analyzed patterns of use and real-world survival outcomes in 370 patients who received ibrutinib for first-line (1 L, n = 35) and relapsed/refractory (R/R, n = 335) CLL between 2014-2018 in BC. Dose reductions and interruptions were frequent in 32% and 27%, respectively. With a median follow-up of 27.6 months, 35% of patients discontinued ibrutinib, primarily for adverse events (AEs) rather than progressive disease. Over the course of treatment, 87% of patients experienced at least one adverse event. The 2-year overall survival (OS) and event-free survival (EFS) were excellent at 83.9% and 76.1%, respectively, with medians not reached. However, patients who discontinued ibrutinib had a median OS of 32.5 months and median EFS of only 3.8 months from time of discontinuation, highlighting the need to minimize toxicity in the real-world.

Allogeneic haematopoietic stem cell transplantation for chronic lymphocytic leukaemia: outcome in a 20-year cohort.

The curative potential of allogeneic haematopoietic stem cell transplant (allo HSCT) in chronic lymphocytic leukaemia CLL is established, with a demonstrated role for graft-versus-leukaemia and less certainty for other factors in determining outcome. The first two decades of CLL patients proceeding to allo HSCT at the Leukaemia/Bone Marrow Transplant Program of British Columbia (n = 49 consecutive, 1991-2009) were studied to clarify factors predicting outcome. The donor was related in 29 (59%) and unrelated in 20 (41%). Conditioning was reduced-intensity in 27 (55%) and myeloablative in 22 (45%). Thirty-one of 49 patients survive with median follow-up of 5 years (0·2-15). Cumulative incidence of non-relapse mortality; complete remission (CR); clearance of fluorescence in situ hybridization (FISH) abnormality and progression at 10 years was 36%; 69%; 55% and 22%. Overall survival (OS) was 63% at 2 years; 55% at 5 years and beyond. Factors predicting OS (P value by log rank <0·05) were: comorbidity index <3, FISH rank (Dohner) and 17p deletion, alemtuzumab pre-HSCT, achievement of CR post-HSCT, donor chimerism >90%, clearance of FISH abnormality post-HSCT and absence of high-grade (3-4) graft-versus-host disease. Results from this province-wide, two-decade cohort demonstrated that a substantial proportion of patients with high-risk CLL become long term disease-free survivors.

Impact of age and treatment institution type on outcomes of patients treated for chronic lymphocytic leukemia in British Columbia, Canada.

Older age has been shown to adversely impact overall survival (OS) in chronic lymphocytic leukemia (CLL) however, prior population-based studies did not analyze the impact of cytogenetic abnormalities or were prior to the availability of ibrutinib. OBJECTIVES: i) We sought to compare outcomes of patients based on their age at treatment to examine if older age has an impact on OS in patients who were treated during the period when fludarabine-rituximab was the standard upfront therapy and when ibrutinib was first introduced and ii) compare outcomes based on whether the patient received primary treatment at an academic or community-based centre. METHODS: The BC Provincial CLL Database, a population-based databasewas used to include patients who have received treatment in British Columbia (BC), Canada between 2004 and 2016. RESULTS: A total of 1122 patients were included (<70 years at treatment, n = 589) with median age at diagnosis 66 years. Younger patients had higher Rai stage (55% vs. 44% stage I-II, p < 0.001), higher lymphocyte count at diagnosis (13 × 109/L vs. 10 × 109/L, p = 0.004), greater proportion with B-symptoms at diagnosis (15% vs 10%, p = 0.004), shorter time from diagnosis to treatment (13.9 months vs. 21.4 months, p = 0.001), higher proportion treated at an academic centre (79% vs. 69%, p < 0.001) and more were treated with fludarabine-rituximab or FCR (69% vs. 42%, p < 0.001) compared to older patients. Older patients had both a significantly (p < 0.001) shorter OS from treatment start (4.7 years) and disease specific survival (8.1 years) than younger patients (median OS and DSS not reached). Of interest, there was no difference in OS between patients treated at an academic centre or community centre (p = 0.087). First-line treatment with chemoimmunotherapy improved OS (HR 0.465, 95% CI: 0.381-.567). CONCLUSIONS: Older age but not treatment-institution type adversely impacts overall survival and CLL survival in treated patients in BC.

Response to tyrosine kinase inhibitor therapy in patients with chronic myelogenous leukemia relapsing in chronic and advanced phase following allogeneic hematopoietic stem cell transplantation.

Tyrosine kinase inhibitors (TKI) have been used to treat relapse of chronic myelogenous leukemia (CML) after allogeneic stem cell transplant (HSCT), with responses seen predominantly in chronic phase (CP) patients. This study aimed to analyze the response to TKI therapy and overall survival for patients relapsing predominantly in advanced phase. We retrospectively reviewed 22 patients treated with imatinib (n=20) and/or dasatinib (n=6) for relapsed CML after HSCT; 8 patients were in CP, and 14 patients had advanced disease. Seven patients also received donor lymphocyte infusions. Hematologic, cytogenetic, and molecular responses were analyzed. Nineteen patients (86%) achieved complete hematologic response (CHR), 17 patients (77%) achieved complete cytogenetic response (CCR), and 14 patients (64%) achieved complete molecular response (CMR). In advanced phase patients, 11 (79%) achieved CHR, 10 (71%) CCR, and 8 (57%) achieved CMR. Grade 3 or 4 cytopenias occurred in 10 cases. With median follow-up of 31.5 months from relapse, 14 (64%) patients remain alive, 13 in CMR. In multivariate analysis, the achievement of CMR was significantly correlated with OS with an odds ratio of 20.5 (95% confidence interval 2.3-182) P=.007. TKI therapy is capable of inducing durable molecular responses for CML relapsing after HSCT, both in chronic and advanced phases. The achievement of CMR appears to be crucial in providing long-term disease control for these patients.

Five new pedigrees with inherited RUNX1 mutations causing familial platelet disorder with propensity to myeloid malignancy.

Familial platelet disorder with propensity to myeloid malignancy (FPD/AML) is an autosomal dominant syndrome characterized by platelet abnormalities and a predisposition to myelodysplasia (MDS) and/or acute myeloid leukemia (AML). The disorder, caused by inherited mutations in RUNX1, is uncommon with only 14 pedigrees reported. We screened 10 families with a history of more than one first degree relative with MDS/AML for inherited mutations in RUNX1. Germ- line RUNX1 mutations were identified in 5 pedigrees with a 3:2 predominance of N-terminal mutations. Several affected members had normal platelet counts or platelet function, features not previously reported in FPD/AML. The median incidence of MDS/AML among carriers of RUNX1 mutation was 35%. Individual treatments varied but included hematopoietic stem cell transplantation from siblings before recognition of the inherited leukemogenic mutation. Transplantation was associated with a high incidence of complications including early relapse, failure of engraftment, and posttransplantation lymphoproliferative disorder. Given the small size of modern families and the clinical heterogeneity of this syndrome, the diagnosis of FPD/AML could be easily overlooked and may be more prevalent than previously recognized. Therefore, it would appear prudent to screen young patients with MDS/AML for RUNX1 mutation, before consideration of sibling hematopoietic stem cell transplantation.

Bendamustine and rituximab as induction therapy in both transplant-eligible and -ineligible patients with mantle cell lymphoma.

Rituximab-containing chemotherapy regimens constitute standard first-line therapy for mantle cell lymphoma (MCL). Since June 2013, 190 patients ≥18 years of age with MCL in British Columbia have been treated with bendamustine and rituximab (BR). The overall response rate to BR was 88% (54% complete response). Of these, 61 of 89 patients (69%) aged ≤65 years received autologous stem cell transplantation and 141 of 190 patients (74%) from the entire cohort received maintenance rituximab. Twenty-three patients (12%) had progressive disease, associated with high risk per the Mantle Cell Lymphoma International Prognostic Index (MIPI), Ki-67 ≥50%, and blastoid/pleomorphic histology. Outcomes were compared with a historical cohort of 248 patients treated with rituximab, cyclophosphamide, doxorubicin, vincristine, and prednisone (R-CHOP; January 2003 to May 2013). Treatment with BR was associated with significant improvements in progression-free survival (PFS), but not overall survival (OS), compared with R-CHOP in the whole cohort (3-year PFS, 66% BR vs 51% R-CHOP, P = .003; 3-year OS, 73% BR vs 66% R-CHOP, P = .054) and in those >65 years of age (3-year PFS, 56% BR vs 35% R-CHOP, P = .001; 3-year OS, 64% BR vs 55% R-CHOP, P = .063). Outcomes in transplanted patients were not statistically significantly different compared with R-CHOP (3-year PFS, 85% BR vs 76% R-CHOP, P = .135; 3-year OS, 90% BR vs 88% R-CHOP, P = .305), although in multivariate analyses, treatment with BR was associated with improved PFS (hazard ratio, 0.40 [95% confidence interval, 0.17-0.94]; P = .036) but not OS. BR is an effective first-line option for most patients with MCL, however, outcomes are suboptimal for those with high-risk features and further studies integrating novel agents are warranted.

Comparison of real-world treatment patterns in chronic lymphocytic leukemia management before and after availability of ibrutinib in the province of British Columbia, Canada.

We performed a retrospective study comparing treatment patterns and overall survival (OS) in chronic lymphocytic leukemia (CLL) patients with the advent of ibrutinib to provide current real-world data. METHODS: Using a provincial population-based database, we analyzed CLL patients who received upfront treatment in British Columbia before ibrutinib availability (1984-2014), during ibrutinib access for: relapse only (2014-2015) and for upfront treatment of patients (with 17p deletion or unfit for chemotherapy) (2015-2016). Analysis included up to third-line treatment. RESULTS: Of 1729 patients meeting inclusion criteria (median age, 66 years; 1466, period 1; 140, period 2; 123, period 3), FR was the most common first-line therapy (35.8 %, 54.3 % and 40.7 %, periods 1-3, respectively) and 18.7 % received ibrutinib upfront in period 3. The most common therapies in relapse were chemoimmunotherapy (36.1 % and 55.6 %, periods 1 and 2, second-line; 29.2 %, period 1, third-line) and ibrutinib (69.8 %, period 3, second-line; 46.4 % and 70.3 %, periods 2 and 3, third-line). OS improved for patients treated in periods 2-3 over period 1 (median OS not reached vs. 11.9 years, p < 0.001; no difference in OS for periods 2-3, p = 0.385). CONCLUSION: Ibrutinib has replaced chemoimmunotherapy as the preferred therapy in relapse. Overall survival has improved over time with access to ibrutinib.

Ultrasensitive Detection of NOTCH1 c.7544_7545delCT Mutations in Chronic Lymphocytic Leukemia by Droplet Digital PCR Reveals High Frequency of Subclonal Mutations and Predicts Clinical Outcome in Cases with Trisomy 12.

NOTCH1 is recurrently mutated in chronic lymphocytic leukemia (CLL), most commonly as a 2-bp frameshift deletion (c.7541_7542delCT). This mutated allele encodes a truncated form of the receptor (p.P2514Rfs∗4) lacking the C-terminal proline, glutamic acid, serine, and threonine (PEST) degradation domain that increases NOTCH1 signaling duration. NOTCH1 mutation has been associated with poor clinical outcomes in CLL. We validated a highly sensitive and quantitative droplet digital PCR assay for the NOTCH1 delCT mutation, which was anticipated to perform well compared with Sanger sequencing and allele-specific PCR. Performance characteristics of this assay were tested on 126 samples from an unselected CLL cohort and a separate cohort of 85 samples from patients with trisomy 12 CLL. The delCT mutation was detected at allele frequencies as low as 0.024%; 25% of unselected cases and 55% of trisomy 12 cases were positive at the 0.024% detection threshold. Mutational burdens ≥1% were significantly associated with shorter overall survival (OS) in patients with trisomy 12+ disease in multivariate analysis (median OS, 9.1 versus 13 years, with hazard ratio of 2.34; P = 0.031). Mutational burdens <1% correlated with shorter OS in univariate, but not multivariate, analyses. These results suggest that droplet digital PCR testing for NOTCH1 delCT mutation may aid in risk stratification and/or disease monitoring in certain subsets of patients with CLL.

The complex genetic landscape of familial MDS and AML reveals pathogenic germline variants.

The inclusion of familial myeloid malignancies as a separate disease entity in the revised WHO classification has renewed efforts to improve the recognition and management of this group of at risk individuals. Here we report a cohort of 86 acute myeloid leukemia (AML) and myelodysplastic syndrome (MDS) families with 49 harboring germline variants in 16 previously defined loci (57%). Whole exome sequencing in a further 37 uncharacterized families (43%) allowed us to rationalize 65 new candidate loci, including genes mutated in rare hematological syndromes (ADA, GP6, IL17RA, PRF1 and SEC23B), reported in prior MDS/AML or inherited bone marrow failure series (DNAH9, NAPRT1 and SH2B3) or variants at novel loci (DHX34) that appear specific to inherited forms of myeloid malignancies. Altogether, our series of MDS/AML families offer novel insights into the etiology of myeloid malignancies and provide a framework to prioritize variants for inclusion into routine diagnostics and patient management.

IPSS poor-risk karyotype as a predictor of outcome for patients with myelodysplastic syndrome following myeloablative stem cell transplantation.

The optimal therapy for myelodysplastic syndrome (MDS) is allogeneic bone marrow (BM) or blood (BSC) stem cell transplantation (SCT), although outcomes are limited by nonrelapse mortality (NRM) and relapse. A retrospective review was performed of 156 patients who underwent SCT (114 BM, 42 BSC) for MDS or secondary acute myelogenous leukemia (sAML) at our institution. Fifty-five patients remain in continuous complete remission: 35 BM recipients and 20 BSC recipients (median follow-up 139 and 89 months, respectively). Estimated 7-year event-free survival (EFS), NRM, and risk of relapse (ROR) are 33% (95% confidence intervals [CI] 25%-43%), 42% (CI 33%-51%), and 25% (CI 17%-33%) for the BM cohort and 45% (CI 32%-64%, P= .07), 32% (CI 18%-47%, P= .15), and 23% (CI 11%-37%, P= .79) for the BSC cohort. Multivariate analysis showed IPSS poor-risk cytogenetics (P< .001), time from diagnosis to SCT (P< .001), FAB subgroup (P= .001), recipients not in complete remission (CR1) at SCT (P= .005), and the development of acute graft-versus-host disease (aGVHD) (P= .04) were all predictive of an inferior EFS. The FAB subgroup (P= .002), poor-risk karyotype (P= .004), and non-CR1 status also correlated with ROR in multivariate analysis. EFS for poor-risk karyotype patients was superior after receiving BSC compared to BM (39% versus 6%, P< .001). SCT outcomes in MDS/sAML are strongly associated with the IPSS cytogenetic risk group, although the use of BSC in poor-risk karyotype patients may lead to a more favorable long-term EFS.

Chronic lymphocytic leukemia patients with HLA-B27 referred for allogeneic hematopoietic stem cell transplantation do not have worse outcomes: Results of a population-based case series analysis in British Columbia, Canada.

Human leukocyte antigen B27 (HLA-B27), associated with spondyloarthritis, was suggested to be protective against chronic lymphocytic leukemia (CLL). It is hypothesized that HLA-B27 patients may have worse outcome in part related to their other comorbidities. OBJECTIVES: We sought to compare the clinical characteristics and outcomes of CLL and small lymphocytic lymphoma (SLL) patients referred for allogeneic hematopoietic stem cell transplantation (allo-HSCT) based on their HLA-B27 status. METHODS: This retrospective population-based case series analyzed CLL/SLL patients who were HLA-typed for potential allo-HSCT in British Columbia, Canada. RESULTS: of 279 CLL/SLL patients referred for potential allo-HSCT, 34 patients were HLA-B27 positive. For HLA-B27 patients, median age at CLL diagnosis was 53.5 years (range, 27-67) and 71% were male. Seven patients had 11q deletion and nine patients had 17p deletion detected prior to first CLL therapy or at relapse. Eleven HLA-B27 patients received allo-HSCT. Two patients developed acute myeloid leukemia. One patient with ankylosing spondylitis had Richter's transformation prior to any CLL therapy. Spondyloarthritis-related disorders were diagnosed in 12 HLA-B27 patients but there was no temporal correlation with development of CLL. Overall survival (OS) and treatment-free survival (TFS) were not significantly different between HLA-B27 patients with or without spondyloarthritis-related disorders. There were no significant differences in clinical characteristics at CLL diagnosis or OS/TFS between HLA-B27 positive and negative patients referred for allo-HSCT. CONCLUSIONS: HLA-B27 positivity does not appear to influence outcome for CLL/SLL patients referred for allo-HSCT. Further studies are needed to evaluate the clinical significance of HLA-B27 in a general CLL population.

Improved survival outcomes with the addition of rituximab to initial therapy for chronic lymphocytic leukemia: a comparative effectiveness analysis in the province of British Columbia, Canada.

Chemoimmunotherapy with rituximab improves survival in clinical trials in upfront chronic lymphocytic leukemia (CLL) treatment. This study compared clinical outcomes with and without rituximab added to first-line chemotherapy in a provincial cohort of CLL patients. Between 1973 and 2014, 1345 patients received CLL treatment: 48% with rituximab, 52% chemotherapy alone. Median overall survival (OS) and treatment-free survival (TFS) were significantly longer with rituximab: OS 8.9 vs. 6.2 years, p < .0001; TFS 3.6 vs. 2.1 years, p < .0001. Addition of rituximab to chemotherapy was a strong independent predictor of mortality with a 32% mortality reduction after controlling for co-variates (age, sex, stage, and treatment with purine analogs). This large population-based study complements clinical trial and registry data demonstrating the benefit of adding rituximab to first-line CLL therapy and adds further evidence of the efficacy of rituximab-based chemoimmunotherapy in a real-world setting.