Unbalanced MYC break-apart FISH patterns indicate the presence of a MYC rearrangement in HGBCL-DH-BCL2

ABSTRACT

Fluorescence in situ hybridization (FISH) using break-apart probes is recommended for identifying high-grade B-cell lymphoma with MYC and BCL2 rearrangements (HGBCL-DH-BCL2). Unbalanced MYC break-apart patterns, in which the red or green signal is lost, are commonly reported as an equivocal result by clinical laboratories. In a cohort of 297 HGBCL-DH-BCL2, 13% of tumors had unbalanced MYC break-apart patterns with loss of red (LR; 2%) or loss of green (LG; 11%) signal. To determine the significance of these patterns, MYC rearrangements were characterized by sequencing in 130 HGBCL-DH-BCL2, including 3 LR and 14 LG tumors. A MYC rearrangement was identified for 71% of tumors with LR or LG patterns, with the majority involving immunoglobulin loci or other recurrent MYC rearrangement partners. The architecture of these rearrangements consistently preserved the rearranged MYC allele, with the MYC gene predicted to be on the derivative chromosome containing the signal that is still present in nearly all cases. MYC protein expression, MYC messenger RNA expression, and the proportion of tumors expressing the dark-zone signature was not significantly different between balanced and unbalanced groups. These results support a recommendation that unbalanced MYC break-apart FISH patterns be reported as positive for MYC rearrangement in the context of diagnosing HGBCL-DH-BCL2.

Assay-guided treatment sequencing in chronic lymphocytic leukemia (CLL): a cost-effectiveness analysis

Costly targeted cancer treatments challenge publicly-funded healthcare systems seeking to align expected benefit with value for money. In 2021, The Canadian Agency for Drugs and Technologies in Health (CADTH) published a provisional funding algorithm for risk-based treatment of chronic lymphocytic leukemia (CLL). We estimate the cost-effectiveness of this algorithm against current standard of care. We constructed a probabilistic Markov model comparing next generation sequencing (NGS) assay-guided front-line treatment of acalabrutinib versus venetoclax with obinutuzumab to a comparator wherein patients initiate acalabrutinib. The primary outcome was the incremental cost-effectiveness ratio (ICER) per quality-adjusted life-year (QALY) gained. Analyses were conducted from the British Columbia healthcare system perspective, with outcomes discounted at 1.5%. Assay informed treatment for patients with CLL resulted in an incremental cost effectiveness ratio of $18,040 (95% CI $16,491-$19,501) per quality adjusted life-year (QALY) gained. The probability of the NGS guided treatment algorithm being cost effective was 80% at a willingness to pay threshold of $50,000 and a corresponding ICER of $18,040. Assay-guided treatment sequencing adds additional costs to healthcare but may be a cost-effective intervention for adult patients with CLL. Integration of real-world evidence would improve the validity and reliability of model estimated for decision-makers.

Spatially Resolved Tumor Microenvironment Predicts Treatment Outcomes in Relapsed/Refractory Hodgkin Lymphoma

PURPOSE

About a third of patients with relapsed or refractory classic Hodgkin lymphoma (r/r CHL) succumb to their disease after high-dose chemotherapy followed by autologous stem-cell transplantation (HDC/ASCT). Here, we aimed to describe spatially resolved tumor microenvironment (TME) ecosystems to establish novel biomarkers associated with treatment failure in r/r CHL.

PATIENTS AND METHODS

We performed imaging mass cytometry (IMC) on 71 paired primary diagnostic and relapse biopsies using a marker panel specific to CHL biology. For each cell type in the TME, we calculated a spatial score measuring the distance of nearest neighbor cells to the malignant Hodgkin Reed Sternberg cells within the close interaction range. Spatial scores were used as features in prognostic model development for post-ASCT outcomes.

RESULTS

Highly multiplexed IMC data revealed shared TME patterns in paired diagnostic and early r/r CHL samples, whereas TME patterns were more divergent in pairs of diagnostic and late relapse samples. Integrated analysis of IMC and single-cell RNA sequencing data identified unique architecture defined by CXCR5+ Hodgkin and Reed Sternberg (HRS) cells and their strong spatial relationship with CXCL13+ macrophages in the TME. We developed a prognostic assay (RHL4S) using four spatially resolved parameters, CXCR5+ HRS cells, PD1+CD4+ T cells, CD68+ tumor-associated macrophages, and CXCR5+ B cells, which effectively separated patients into high-risk versus low-risk groups with significantly different post-ASCT outcomes. The RHL4S assay was validated in an independent r/r CHL cohort using a multicolor immunofluorescence assay.

CONCLUSION

We identified the interaction of CXCR5+ HRS cells with ligand-expressing CXCL13+ macrophages as a prominent crosstalk axis in relapsed CHL. Harnessing this TME biology, we developed a novel prognostic model applicable to r/r CHL biopsies, RHL4S, opening new avenues for spatial biomarker development.

Frontline therapy with bendamustine rituximab (BR) and rituximab cyclophosphamide vincristine prednisone (RCVP) confers similar long-term outcomes in patients with treatment naïve Waldenström macroglobulinemia in a real-world setting: a population-based analysis

We report on outcomes of 111 patients with treatment naïve Waldenström macroglobulinemia (TN WM) treated with frontline bendamustine-rituximab (BR) (n = 57) or rituximab-cyclophosphamide-vincristine-prednisone (RCVP) (n = 54). Median follow-up was 60.7 months (range 1.9-231.6). Median progression-free survival (PFS) was 60.5 months (95% CI 47.6-73.4) for BR and 79.0 months (95% CI 31.3-126.8) for RCVP (p = .96). Median overall survival (OS) was not reached for BR and 153.4 months (95% CI 114.5-192.4) for RCVP (p = .37). While overall and major response rates did not differ between treatment groups, BR had numerically higher rate of very good partial response or better response (51% vs. 37%, p = .30) and complete response (26% vs. 13%, p = .13). RCVP confers comparable outcomes to BR in a real-world population of TN WM patients and remains an effective regimen, particularly when tolerance or frailty is an issue, or in resource-limited settings.

The influence of immunodeficiency, disease features, and patient characteristics on survival in plasmablastic lymphoma

ABSTRACT

Plasmablastic lymphoma (PBL) is a rare and aggressive non-Hodgkin lymphoma associated with immunodeficiency, characterized by uncertain treatment approaches and an unfavorable prognosis. We conducted a multicenter, international, retrospective cohort study, aiming to characterize the clinical features, risk factors, and outcomes of patients with PBL. Data were collected from 22 institutions across 4 countries regarding patients diagnosed with PBL between 1 January 1999 and 31 December 2020. Survival risk factors were analyzed using both univariate and multivariate regression models. Overall survival (OS) was calculated using Kaplan-Meier statistics. First-line treatment regimens were stratified into standard- and higher-intensity regimens, and based on whether they incorporated a proteasome inhibitor (PI). A total of 281 patients (median age, 55 years) were included. Immunodeficiency of any kind was identified in 144 patients (51%), and 99 patients (35%) had HIV-positive results. The 5-year OS for the entire cohort was 36% (95% confidence interval, 30%-42%). In multivariate analysis, inferior OS was associated with Epstein-Barr virus-negative lymphoma, poor performance status, advanced stage, and bone marrow involvement. In an independent univariate analysis, the international prognostic index was associated with OS outcomes. Neither immunosuppression nor HIV infection, specifically, influenced OS. Among patients treated with curative intent (n = 234), the overall response rate was 72%. Neither the intensity of the treatment regimen nor the inclusion of PIs in first-line therapy was associated with OS. In this large retrospective study of patients with PBL, we identified novel risk factors for survival. PBL remains a challenging disease with poor long-term outcomes.

Chronic Lymphocytic Leukemia IGHV Somatic Hypermutation Detection by Targeted Capture Next-Generation Sequencing

BACKGROUND

Somatic hypermutation (SHM) status of the immunoglobulin heavy variable (IGHV) gene plays a crucial role in determining the prognosis and treatment of patients with chronic lymphocytic leukemia (CLL). A common approach for determining SHM status is multiplex polymerase chain reaction and Sanger sequencing of the immunoglobin heavy locus; however, this technique is low throughput, is vulnerable to failure, and does not allow multiplexing with other diagnostic assays.

METHODS

Here we designed and validated a DNA targeted capture approach to detect immunoglobulin heavy variable somatic hypermutation (IGHV SHM) status as a submodule of a larger next-generation sequencing (NGS) panel that also includes probes for ATM, BIRC3, CHD2, KLHL6, MYD88, NOTCH1, NOTCH2, POT1, SF3B1, TP53, and XPO1. The assay takes as input FASTQ files and outputs a report containing IGHV SHM status and V allele usage following European Research Initiative on CLL guidelines.

RESULTS

We validated the approach on 35 CLL patient samples, 34 of which were characterized using Sanger sequencing. The NGS panel identified the IGHV SHM status of 34 of 35 CLL patients. We showed 100% sensitivity and specificity among the 33 CLL samples with both NGS and Sanger sequencing calls. Furthermore, we demonstrated that this panel can be combined with additional targeted capture panels to detect prognostically important CLL single nucleotide variants, insertions/deletions, and copy number variants (TP53 copy number loss).

CONCLUSIONS

A targeted capture approach to IGHV SHM detection can be integrated into broader sequencing panels, allowing broad CLL prognostication in a single molecular assay.

Outcomes of patients with blastoid and pleomorphic variant mantle cell lymphoma

Mantle cell lymphoma (MCL) is a B-cell non-Hodgkin lymphoma; data indicate that blastoid and pleomorphic variants have a poor prognosis. We report characteristics and outcomes of patients with blastoid/pleomorphic variants of MCL. We retrospectively studied adults with newly diagnosed MCL treated from 2000 to 2015. Primary objectives were to describe progression-free survival (PFS) and overall survival (OS). Secondary objectives included characterization of patient characteristics and treatments. Of the 1029 patients with MCL studied, a total of 207 neoplasms were blastoid or pleomorphic variants. Median follow-up period was 82 months (range, 0.1-174 months); median PFS was 38 months (95% confidence interval [CI], 28-66) and OS was 68 months (95% CI, 45-96). Factors associated with PFS were receipt of consolidative autologous hematopoietic transplantation (auto-HCT; hazard ratio [HR], 0.52; 95% CI, 0.31-0.80; P < .05), MCL International Prognostic Index (MIPI) intermediate (HR, 2.3; 95% CI, 1.2-4.3; P < .02) and high (HR, 3.8; 95% CI, 2.0-7.4; P < .01) scores, and complete response to induction (HR, 0.29 (95% CI, 0.17-0.51). Receipt of auto-HCT was not associated with OS (HR, 0.69; 95% CI, 0.41-1.16; P = .16) but was associated with MIPI intermediate (HR, 5.7; 95% CI, 2.5-13.2; P < .01) and high (HR, 10.8; 95% CI, 4.7-24.9; P < .01) scores. We report outcomes in a large cohort of patients with blastoid/pleomorphic variant MCL. For eligible patients, receipt of auto-HCT after induction was associated with improved PFS but not OS. Higher MIPI score and auto-HCT ineligibility were associated with worse survival.

Canadian evidence-based guideline for treatment of relapsed/refractory chronic lymphocytic leukemia

Following the recent publication of Canadian evidence-based guidelines for frontline treatment of chronic lymphocytic leukemia (CLL), the same group of clinicians developed guidelines for CLL in the relapsed/refractory (R/R) setting. The treatment of R/R CLL has changed significantly in the past few years, with many novel therapeutics available to hematologists across the country. These guidelines aim to standardize the management of CLL in the relapsed/refractory setting, using the best evidence currently available.

Relapse Timing Is Associated With Distinct Evolutionary Dynamics in Diffuse Large B-Cell Lymphoma

PURPOSE

Diffuse large B-cell lymphoma (DLBCL) is cured in more than 60% of patients, but outcomes remain poor for patients experiencing disease progression or relapse (refractory or relapsed DLBCL [rrDLBCL]), particularly if these events occur early. Although previous studies examining cohorts of rrDLBCL have identified features that are enriched at relapse, few have directly compared serial biopsies to uncover biological and evolutionary dynamics driving rrDLBCL. Here, we sought to confirm the relationship between relapse timing and outcomes after second-line (immuno)chemotherapy and determine the evolutionary dynamics that underpin that relationship.

PATIENTS AND METHODS

Outcomes were examined in a population-based cohort of 221 patients with DLBCL who experienced progression/relapse after frontline treatment and were treated with second-line (immuno)chemotherapy with an intention-to-treat with autologous stem-cell transplantation (ASCT). Serial DLBCL biopsies from a partially overlapping cohort of 129 patients underwent molecular characterization, including whole-genome or whole-exome sequencing in 73 patients.

RESULTS

Outcomes to second-line therapy and ASCT are superior for late relapse (>2 years postdiagnosis) versus primary refractory (<9 months) or early relapse (9-24 months). Diagnostic and relapse biopsies were mostly concordant for cell-of-origin classification and genetics-based subgroup. Despite this concordance, the number of mutations exclusive to each biopsy increased with time since diagnosis, and late relapses shared few mutations with their diagnostic counterpart, demonstrating a branching evolution pattern. In patients with highly divergent tumors, many of the same genes acquired new mutations independently in each tumor, suggesting that the earliest mutations in a shared precursor cell constrain tumor evolution toward the same genetics-based subgroups at both diagnosis and relapse.

CONCLUSION

These results suggest that late relapses commonly represent genetically distinct and chemotherapy-naïve disease and have implications for optimal patient management.

Time to progression of disease and outcomes with second-line BTK inhibitors in relapsed/refractory mantle cell lymphoma

Time to progression of disease (POD) after first-line (1L) therapy is prognostic in mantle cell lymphoma (MCL), although studies have included a broad range of 1L, second-line (2L), and subsequent lines of therapy. The purpose of this study was to evaluate the factors predicting outcomes in patients with relapsed/refractory (R/R) MCL exclusively initiating 2L Bruton's tyrosine kinase inhibitors (BTKis) after 1L rituximab-containing therapy. Patients were accrued from 8 international centers (7 main, 1 validation cohort). Multivariable models evaluating the association between time to POD and clinical/pathologic factors were constructed and converted into nomograms and prognostic indexes predicting outcomes in this population. A total of 360 patients were included, including 160 in the main cohort and 200 in the validation cohort. Time to POD, Ki67 ≥ 30%, and MCL International Prognostic Index (MIPI) were associated with progression-free survival (PFS2) and overall survival (OS2) from the start of 2L BTKis. C-indexes were consistently ≥0.68 in both cohorts. Web/application-based calculators based on nomograms and prognostic indexes to estimate PFS2 and OS2 were constructed. The 2L BTKi MIPI identifies 3 groups with distinct 2-year PFS2, including high risk (14%), intermediate risk (50%), and low risk (64%). Time to POD, Ki67, and MIPI are associated with survival outcomes in patients with R/R MCL receiving 2L BTKis. Simple clinical models incorporating these variables may assist in planning for alternative therapies such as chimeric antigen receptor T-cell therapy, allogeneic stem cell transplantation, or novel agents with alternative mechanisms of action.

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.

Relapse timing is associated with distinct evolutionary dynamics in DLBCL

Diffuse large B-cell lymphoma (DLBCL) is cured in over 60% of patients, but outcomes are poor for patients with relapsed or refractory disease (rrDLBCL). Here, we performed whole genome/exome sequencing (WGS/WES) on tumors from 73 serially-biopsied patients with rrDLBCL. Based on the observation that outcomes to salvage therapy/autologous stem cell transplantation are related to time-to-relapse, we stratified patients into groups according to relapse timing to explore the relationship to genetic divergence and sensitivity to salvage immunochemotherapy. The degree of mutational divergence increased with time between biopsies, yet tumor pairs were mostly concordant for cell-of-origin, oncogene rearrangement status and genetics-based subgroup. In patients with highly divergent tumors, several genes acquired exclusive mutations independently in each tumor, which, along with concordance of genetics-based subgroups, suggests that the earliest mutations in a shared precursor cell constrain tumor evolution. These results suggest that late relapses commonly represent genetically distinct and chemotherapy-naïve disease.

Genetic subgroups inform on pathobiology in adult and pediatric Burkitt lymphoma

Burkitt lymphoma (BL) accounts for most pediatric non-Hodgkin lymphomas, being less common but significantly more lethal when diagnosed in adults. Much of the knowledge of the genetics of BL thus far has originated from the study of pediatric BL (pBL), leaving its relationship to adult BL (aBL) and other adult lymphomas not fully explored. We sought to more thoroughly identify the somatic changes that underlie lymphomagenesis in aBL and any molecular features that associate with clinical disparities within and between pBL and aBL. Through comprehensive whole-genome sequencing of 230 BL and 295 diffuse large B-cell lymphoma (DLBCL) tumors, we identified additional significantly mutated genes, including more genetic features that associate with tumor Epstein-Barr virus status, and unraveled new distinct subgroupings within BL and DLBCL with 3 predominantly comprising BLs: DGG-BL (DDX3X, GNA13, and GNAI2), IC-BL (ID3 and CCND3), and Q53-BL (quiet TP53). Each BL subgroup is characterized by combinations of common driver and noncoding mutations caused by aberrant somatic hypermutation. The largest subgroups of BL cases, IC-BL and DGG-BL, are further characterized by distinct biological and gene expression differences. IC-BL and DGG-BL and their prototypical genetic features (ID3 and TP53) had significant associations with patient outcomes that were different among aBL and pBL cohorts. These findings highlight shared pathogenesis between aBL and pBL, and establish genetic subtypes within BL that serve to delineate tumors with distinct molecular features, providing a new framework for epidemiologic, diagnostic, and therapeutic strategies.

The clinical impact of COVID-19 on patients with cancer in British Columbia: An observational study

Objective

We evaluated survival outcomes for patients with cancer and COVID-19 in this population-based study.

Methods

A total of 631 patients who tested positive for severe acute respiratory syndrome coronavirus 2 and were seen at BC Cancer between 03/03/2020 and 01/21/2021 were included, of whom 506 had a diagnosis of cancer and PCR-confirmed positive test for coronavirus disease 2019. Patient clinical characteristics were retrospectively reviewed and the influence of demographic data, cancer diagnosis, comorbidities, and anticancer treatment(s) on survival following severe acute respiratory syndrome coronavirus 2 infection were analyzed.

Results

Age ≥65 years (Hazard Ratio [HR] 4.77, 95% Confidence Interval [CI] 2.72-8.35, P < 0.0001), those with Eastern Cooperative Oncology Group Performance Status ≥2 (HR 8.36, 95% CI 2.89-24.16, P < 0.0001), hypertension (HR 3.17, 95% CI 1.77-5.66, P < 0.0001), and metastatic/advanced stage (HR 3.70, 95% CI 1.77-7.73, P < 0.0001) were associated with worse coronavirus disease 2019 specific survival outcomes following severe acute respiratory syndrome coronavirus 2 infection. Patients with lung cancer had the highest 30-day COVID-19 specific mortality (25.0%), followed by genitourinary (18.1%), gastrointestinal (16.0%), and other cancer types (<10.0%). Patients with the highest 30-day coronavirus disease 2019 specific mortality according to treatment type were those on chemotherapy (23.0%), rituximab (22.2%), and immunotherapy (16.7%) while patients on hormonal treatments (2.2%) had better survival outcomes (P = 0.041) compared to those on other anticancer treatments.

Conclusion

This study provides further evidence that patients with cancer are at increased risk of mortality from coronavirus disease 2019 and emphasizes the need for vaccination.

Clinicopathological characteristics and long-term outcomes of plasmablastic lymphoma in British Columbia

Plasmablastic lymphoma (PBL) is an aggressive and rare subtype of non-Hodgkin lymphoma with no standard-of-care therapy. We reviewed all patients diagnosed with histologically confirmed PBL in British Columbia, Canada between 1997 and 2019. Overall, 42 patients were identified, including 15 (36%) positive for HIV and nine (21%) on chronic immunosuppression. Curative-intent treatment consisting primarily of cyclophosphamide, doxorubicin, vincristine and prednisone was administered to 31 patients, of which 74% achieved response, however 61% relapsed after a median of 7.5 months. At a median follow-up of eight years for the whole cohort, five-year progression-free survival (PFS) and overall survival (OS) were 18% [95% confidence interval (CI): 6%, 30%] and 22% (95% CI: 8%, 36%) with median eight and 15 months respectively. There were no differences in relapse rate (p = 0.962), PFS (p = 0.228) or OS (p = 0.340) according to immune status. For those treated with curative intent, five-year PFS and OS were 24% (95% CI: 8%, 40%) and 31% (95% CI: 13%, 49%) with median 18 and 27 months respectively. In this population-based cohort of PBL patients spanning 20 years, survival outcomes were poor. Ultimately, further research is needed to develop more effective treatment strategies and to improve survival for patients.

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.

Conservative Management of Presumed Fetal Anemia Secondary to Maternal Chemotherapy for Acute Myeloid Leukemia

Acute myeloid leukemia occurs rarely during pregnancy. When it is diagnosed remote from term, treatment in the form of daunorubicin plus cytarabine induction with consolidative cytarabine is typically undertaken after the first trimester. There is little data to guide fetal monitoring, in particular, whether and how often middle cerebral artery peak systolic velocity (MCA PSV) should be measured to screen for fetal anemia. Cytarabine may be particularly myelosuppressive to the fetus, but information pertaining to the management of this complication is also lacking in published literature. To our knowledge, we present the first case of presumed severe fetal anemia related to in utero exposure to chemotherapy that was managed conservatively with close sonographic monitoring, including serial measurement of MCA PSV. This case suggests that in the absence of hydrops fetalis or other signs of fetal decompensation, expectant management with ultrasound twice weekly, including MCA PSV, is appropriate. Ultrasounds may be decreased to weekly when MCA PSV does not suggest fetal anemia. Screening for fetal anemia can provide helpful information to guide the timing of chemotherapy administration and delivery. Key Points Chemotherapy for acute myeloid leukemia can cause fetal anemia.Fetal MCA PSV can be used to safely and effectively screen for fetal anemia.Observation of fetal anemia due to chemotherapy is reasonable, in the absence of hydrops.Monitoring of fetal MCA PSV can help guide timing of chemotherapy and delivery.

Using blood wisely in oncology patients: An institutional analysis of the Choosing Wisely Canada restrictive transfusion strategy guidelines

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Background: Numerous studies support the safety of single-unit red red blood cell (RBC) transfusions and restrictive pre-transfusion hemoglobin (Hg) thresholds (≤ 70-80 g/L) among diverse populations of hospitalized patients, including those with malignancies on myelosuppressive systemic therapy. Using Blood Wisely is a national Choosing Wisely Canada (CWC) initiative that challenges hospitals to benchmark themselves on evidence-informed restrictive transfusion strategies, with the aim to decrease inappropriate RBC transfusions in Canada. We assessed transfusion practices among oncology inpatients at BC Cancer Vancouver Centre as part of this initiative and performed an exploratory analysis among outpatients. Methods: BC Cancer Vancouver RBC transfusion records were obtained for the period of October 2019-September 2020. The percentage of single-unit transfusions and transfusions for Hg ≤ 80 g/L were measured, to assess adherence to CWC targets of ≥ 65% and ≥ 80%, respectively, for these metrics. Univariate analyses were used to compare treatment variables and transfusion outcomes. Results: During the 1-year audit period, 120 inpatient and 586 outpatient RBC transfusions occurred. For inpatient transfusions, 40.8% (n = 49) were single-unit and 79.2% (n = 95) were for Hg ≤ 80 g/L. For outpatient transfusions, 11.8% (n = 69) were single-unit and 65.7% (n = 304) were for Hg ≤ 80 g/L. Outpatients and patients with solid malignancies were more likely to receive multiple-unit transfusions, compared to inpatients (p < 0.001) and patients with hematological malignancies (p < 0.001), respectively. Patients with solid malignancies and those on active treatment were more likely to be transfused when Hg was > 80 g/L, compared to patients with hematological malignancies (p = 0.004) and those off treatment (p = 0.003), respectively. Multiple RBC units were more likely to transfused when the interval from pre-transfusion bloodwork to receipt of transfusion was > 3 days (p = 0.029). Conclusions: A high rate of inappropriate RBC transfusions are being ordered for oncology patients at our institution, in discordance with CWC restrictive transfusion strategy guidelines. Quality improvement interventions are planned to adopt best practices in transfusion medicine in this high-use population.[Table: see text]

Outcome of limited-stage nodular lymphocyte-predominant Hodgkin lymphoma and the impact of a PET-adapted approach

Radiotherapy (RT) is typically incorporated into the treatment of limited-stage nodular lymphocyte-predominant Hodgkin lymphoma (NLPHL), although it remains unknown whether chemotherapy alone may be suitable in select patients. We evaluated outcomes of limited-stage NLPHL at BC Cancer on the basis of era-specific guidelines: routine RT era, 1995 to 2005 (n = 36), combined modality with 2 cycles of doxorubicin, bleomycin, vinblastine, dacarbazine (ABVD) chemotherapy followed by RT or RT alone; positron emission tomography (PET) era, after 2005 (n = 63), ABVD alone (4 cycles) if the PET scan after the second cycle of ABVD (PET2) is negative, or treatment is changed to RT if PET2 is positive. Median age of patients was 38 years (range, 16-82 years), 73% were male, and 43% had stage II. With a median follow-up of 10.5 years for all patients, 5-year progression-free survival (PFS) was 91% [corrected] and was 97% for overall survival (OS), with no difference by treatment era (PFS, P = .15; [corrected] OS, P = .35). For the 49 patients who had a PET2 scan, 86% were PET negative and 14% were PET positive by Deauville criteria with 5-year PFS rates of 92% and 80% (P = .87) [corrected], respectively. This is the largest study of a PET-adapted approach in NLPHL and supports that ABVD alone may be a viable option in select patients with a negative PET2 scan, with consideration of acute and long-term toxicities.

Outcomes after initial refusal of curative treatment in patients with Hodgkin’s lymphoma in British Columbia

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Background: Classical Hodgkin lymphoma (cHL) is considered a highly curable cancer. With standard combination chemotherapy regimens, long-term survival exceeds 95% for limited-stage and 85% for advanced-stage patients. Despite these excellent outcomes some patients delay or decline conventional treatment for cHL. We retrospectively assessed the impact of initial treatment refusal on outcomes of patients with cHL in British Columbia (BC). Methods: Using the BC Cancer Lymphoid Cancer Database, we identified all patients aged 18-70 diagnosed between 1st Jan 1999- 31st Dec 2020 that had documented treatment refusal at initial presentation (‘refusers’ defined as not receiving or delaying treatment > 16 weeks). We identified a control cohort (min. 3 controls/refuser) treated within 8 weeks of diagnosis, matched for age, stage, diagnosis date within 3 years, and blinded for outcome. All patients had centrally reviewed biopsies and were treated with ABVD or ABVD-like regimens +/- radiotherapy if appropriate. Patient and disease characteristics at baseline and at time of treatment were analyzed with Chi-squared test and one-way ANOVA test. The Kaplan-Meier method was used to assess progression-free survival (PFS) and overall survival (OS), and statistical significance between groups was determined using the log-rank test. Results: We identified a cohort of 15 patients who initially refused treatment and 47 matched controls. The control cohort was well-matched, with no statistically significant differences in baseline characteristics (age, sex, Ann Arbor stage, B symptoms, International Prognostic Score (IPS) score, ECOG PS, and disease bulk) between groups. The most common reason for initial treatment refusal was to pursue alternative therapy (73%). 13 of 15 refusers eventually accepted treatment (mean time to treatment 76 weeks [range 26-214] vs. 5 weeks [range 1-8] for controls, p < 0.001). At time of treatment, the proportion of refusers with advanced-stage disease increased from 20% to 62% (p = 0.03) and had an associated alteration of treatment plan, and 62% of patients developed higher risk disease with increased IPS score (p = 0.02). At median follow-up of 5 years (0.4-21 years) for all living patients, estimated 5-year PFS was 65% vs 84%, and 5-year OS was 93% vs 98% for refusers and controls respectively. With extended follow up, 13% of refusers (1 late death at 8 years) compared to only 4% of controls died of cHL specifically. Conclusions: This study highlights the impact of treatment refusal in this highly curable malignancy. Initial refusal of treatment is associated with progression of stage, worsening prognostic score, escalation to more prolonged treatment than required at diagnosis, and increased risk of death from cHL. This analysis may help to provide guidance to counselling physicians, as well as inform patients who may be considering alternatives to standard of care for cHL.

Burkitt Lymphoma International Prognostic Index

PURPOSE

Burkitt lymphoma (BL) has unique biology and clinical course but lacks a standardized prognostic model. We developed and validated a novel prognostic index specific for BL to aid risk stratification, interpretation of clinical trials, and targeted development of novel treatment approaches.

METHODS

We derived the BL International Prognostic Index (BL-IPI) from a real-world data set of adult patients with BL treated with immunochemotherapy in the United States between 2009 and 2018, identifying candidate variables that showed the strongest prognostic association with progression-free survival (PFS). The index was validated in an external data set of patients treated in Europe, Canada, and Australia between 2004 and 2019.

RESULTS

In the derivation cohort of 633 patients with BL, age ≥ 40 years, performance status ≥ 2, serum lactate dehydrogenase > 3× upper limit of normal, and CNS involvement were selected as equally weighted factors with an independent prognostic value. The resulting BL-IPI identified groups with low (zero risk factors, 18% of patients), intermediate (one factor, 36% of patients), and high risk (≥ 2 factors, 46% of patients) with 3-year PFS estimates of 92%, 72%, and 53%, respectively, and 3-year overall survival estimates of 96%, 76%, and 59%, respectively. The index discriminated outcomes regardless of HIV status, stage, or first-line chemotherapy regimen. Patient characteristics, relative size of the BL-IPI groupings, and outcome discrimination were consistent in the validation cohort of 457 patients, with 3-year PFS estimates of 96%, 82%, and 63% for low-, intermediate-, and high-risk BL-IPI, respectively.

CONCLUSION

The BL-IPI provides robust discrimination of survival in adult BL, suitable for use as prognostication and stratification in trials. The high-risk group has suboptimal outcomes with standard therapy and should be considered for innovative treatment approaches.

Outcome of elderly patients with classical Hodgkin lymphoma (HL) in British Columbia

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Background: Outcomes in elderly patients (pts) with Hodgkin lymphoma (HL) have traditionally been poor. We evaluated the survival of elderly pts (>60 years [y]) with classical HL in British Columbia (BC). Methods: All pts aged >60 y newly diagnosed with classical HL from 1961 to 2019 were identified in the BC Cancer Lymphoid Cancer Database. Limited stage was defined as non-bulky (<10 cm) stage 1A/IB or 2A (before 2000 1B = advanced stage), with the remainder considered advanced stage. Results: Following exclusions (HIV positive n=4, incomplete data n=21, prior or concurrent other lymphoproliferative disease n=67), 713 pts were identified. With a median follow up of 6.0 y (0.1 - 24.0 y) in living pts, there has been an improvement in 5 y DSS/OS (both p<.001) by decade comparison: 1960s (n=52) 25%/17%; 1970s (n=75) 38%/31%; 1980s (n=90) 51%/43%; 1990s (n=115) 53%/42%; 2000s (n=180) 66%/57%; 2010s (n=201) 63%/53%. To account for advances in diagnosis, staging, supportive care, and therapy in the modern era, we evaluated the outcome of pts diagnosed since 01/1995. A total of 368 pts were treated with curative intent (Table). Most pts received multi-agent chemotherapy (n=359, 98%: ABVD[like] n=351, alkylator-based n=7, CHOP n=1), 8 pts had radiotherapy (RT) alone, and 1 pt had surgery (primary CNS HL). The 5 y DSS, PFS, and OS were 74%, 57%, and 62%, respectively. Increasing age was associated with inferior outcomes (5 y DSS/PFS/OS): 61-70 y (81%/70%/74%), 71-80 y (69%/47%/52%), and >80 y (59%/27%/31%) (DSS p=.011; PFS p<.0001; OS p<.0001). Of 318 pts that received bleomycin, 60 (19%) developed pulmonary toxicity, including 22 cases that occurred after cycles 1 and 2. Overall, 24/368 pts (7%) died of acute treatment toxicity (pulmonary [bleomycin n=10, radiation n=1], infection n=10, cardiac n=3). There was no association between age and developing bleomycin (p=.80) or lethal treatment toxicities (p=.74). Conclusions: The outcome of elderly pts with HL has improved in recent decades. However, treatment related toxicity remains a concern and use of multi-agent chemotherapy, particularly bleomycin-containing regimens, should be undertaken with caution. [Table: see text]

Minimal relapse risk and early normalization of survival for patients with Burkitt lymphoma treated with intensive immunochemotherapy: an international study of 264 real-world patients

Non-endemic Burkitt lymphoma (BL) is a rare germinal centre B-cell-derived malignancy with the genetic hallmark of MYC gene translocation and with rapid tumour growth as a distinct clinical feature. To investigate treatment outcomes, loss of lifetime and relapse risk in adult BL patients treated with intensive immunochemotherapy, retrospective clinic-based and population-based lymphoma registries from six countries were used to identify 264 real-world patients. The median age was 47 years and the majority had advanced-stage disease and elevated LDH. Treatment protocols were R-CODOX-M/IVAC (47%), R-hyper-CVAD (16%), DA-EPOCH-R (11%), R-BFM/GMALL (25%) and other (2%) leading to an overall response rate of 89%. The two-year overall survival and event-free survival were 84% and 80% respectively. For patients in complete remission/unconfirmed, the two-year relapse risk was 6% but diminished to 0·6% for patients reaching 12 months of post-remission event-free survival (pEFS12). The loss of lifetime for pEFS12 patients was 0·4 (95% CI: -0·7 to 2) months. In conclusion, real-world outcomes of adult BL are excellent following intensive immunochemotherapy. For pEFS12 patients, the relapse risk was low and life expectancy similar to that of a general population, which is important information for developing meaningful follow-up strategies with increased focus on survivorship and less focus on routine disease surveillance.