The impact of Agent Orange exposure on prognosis and management in patients with chronic lymphocytic leukemia: a National Veteran Affairs Tumor Registry Study

Treatment Patterns and Outcomes in U.S. Military Veterans Diagnosed With Chronic Lymphocytic Leukemia (CLL)

INTRODUCTION

U.S. veterans in the Veterans Affairs (VA) Healthcare System are managed in a national single-payer system with access to FDA-approved therapies. Prescribing patterns and outcomes of patients with CLL manage in the VA system are described.

PATIENTS AND METHODS

This is a retrospective analysis of adult patients diagnosed with CLL managed in the VA from January 1999 through December 2020. First line treatment patterns are trended over 20 years. Factors associated with survival were analyzed in both untreated and treated patients.

RESULTS

In the final analysis, 16,331 patients with CLL were included. The median overall survival (OS) for the whole cohort was 8.7 years (95% confidence interval [CI], 8.6-8.9). The median OS from diagnosis was 8.9 years (95% CI, 8.6-9.2 in untreated patients with CLL. In treated patients, the median time to first line treatment was 1.9 years (range, 0-21 years), and the median OS from initiation of treatment was 5.0 years (95% CI, 4.8-5.2). First line treatments varied over time, consistent with FDA approval of targeted therapies. Exposure to targeted therapies as either first line or in subsequent lines of therapy was associated longer survival: median OS of 8.5 years (95% CI, 8.0-9.1) compared to 3.5 years (95% CI, 3.5-3.9) in patients who never received targeted therapy (P < .0001).

CONCLUSION

Patients treated in the VA have received therapies in line with current evidence-based treatment practices over the past 20 years. Treatment with targeted therapies is associated with longer median OS both in the first line and relapsed/refractory setting.

Agent Orange Exposure, Transformation From MGUS to Multiple Myeloma, and Outcomes in Veterans

BACKGROUND

Multiple myeloma (MM) accounts for 1% to 2% of all cancers. Exposure to the pesticide Agent Orange (AO) has been established as a potential risk factor for the development of monoclonal gammopathy of undetermined significance (MGUS) and, subsequently, MM in Vietnam War veterans.

METHODS

This study explored variation in survival related to AO exposure, transformation from MGUS to MM, and covariates. Vietnam War veterans with MM or MGUS were identified in Veterans Health Administration (VHA) health records data. Cox proportional hazards models analyzed survival as a function of AO, race, ethnicity, body mass index, nicotine dependence, alcohol use disorder, Charlson Comorbidity Index, and treatment. Autologous hematopoietic cell transplantation for MM was defined by procedure codes.

RESULTS

In the VHA 16,366 patients were identified: 11,112 patients diagnosed with MGUS and 7261 with MM during fiscal years 2010 to 2015 were identified; 12% (n = 2007) had both diagnoses. No statistically significant difference in the rate of transformation from MGUS to MM in the AO exposed and AO not exposed groups was found. In survival models, AO exposure was associated with slightly lower mortality. Alcohol use disorder, nicotine dependence, older age, and greater comorbidity burden increased mortality risk. Black race, female sex, obesity/overweight, and hematopoietic cell transplantation for patients with MM were protective factors. AO exposure was associated with decreased mortality for both MM/MGUS groups. Transformation increased mortality risk for patients with MGUS and decreased mortality risk for patients with MM.

CONCLUSIONS

Because AO exposure is a nonmodifiable risk factor, focus should be placed on modifiable risk factors (eg, nicotine dependence, alcohol and drug use disorders, underlying comorbid conditions) as these were associated with worse outcomes. Future studies should examine the correlation of AO exposure, cytogenetics, and clinical outcomes in these veterans to best identify their disease course and optimize their care in the latter part of their life.

Outcomes in chronic lymphocytic leukemia patients on novel agents in the US Veterans Health Administration System

The US veteran population has a high proportion of chronic lymphocytic leukemia (CLL) risk factors. Using the Veterans Health Administration (VHA) population, we conducted a retrospective chart review of 1205 CLL patients who initiated treatment with a novel oral agent. For 1L ibrutinib, 33% (n = 107) discontinued therapy during the study, of which 64% discontinued due to adverse events (AEs). For relapsed/refractory (R/R) ibrutinib, 35% (n = 262) discontinued therapy, of which 63% discontinued due to AEs. For R/R venetoclax, 31% (n = 27) discontinued therapy, of which 41% were due to AEs. For idelalisib, 84% (n = 41) discontinued therapy, of which 54% were due to AEs. This real-world study suggests that AEs play an important role in dose reductions and discontinuations; however, physician inexperience in using these drugs when they were first introduced could be part of what is leading to these negative outcomes.

On the front line: first choice pharmacotherapeutics for chronic lymphocytic leukemia

INTRODUCTION

Chronic lymphocytic leukemia (CLL) is a common hematologic malignancy with a highly variable clinical course. Frontline treatments include cytotoxic chemotherapies, immunotherapies, and small molecule inhibitors. Clinical and molecular factors guide treatment initiation and selection. Over the last decade, refinement of CLL risk stratification tools and growth of the arsenal of effective therapeutics have profoundly improved outcomes. These advances have concurrently increased the complexity of managing the early phases of treatment.

AREAS COVERED

This review describes the factors considered in the determination of first-line treatment of CLL. Areas of emphasis include assessment of patient fitness, disease classification and risk stratification, and the mechanisms, efficacy, and toxicities associated with available pharmacotherapeutics.

EXPERT OPINION

Multiple different treatments may be appropriate for a specific clinical scenario, and selection among them requires discussion of relative risks and benefits. Advances in frontline CLL treatment will continue to shift the treatment paradigm toward prioritizing quality of life alongside survival, limiting treatment and toxicity, and the development of biologically rational synergistic drug combinations and sequences.