Work Disability and Return to Work After Treatment for Acute Lymphoblastic Leukemia: A Danish Nationwide Cohort Study

Purpose

Most adult patients diagnosed with acute lymphoblastic leukemia (ALL) are below retirement age. The overall survival of patients with ALL has improved with implementation of high intensity pediatric-inspired treatment protocols. However, this treatment comes with a risk of long-term complications, which could affect the ability to work. The aim of this study was to investigate the risk of disability pension (DP) and return to work (RTW) for patients with ALL.

Patients and Methods

Patients aged 18-60 years diagnosed with ALL between 2005 and 2019 were identified in the Danish National Acute Leukemia Registry. Each patient was matched with five comparators from the general population on birth year, sex, and Charlson Comorbidity Index. The Aalen-Johansen estimator was used to calculate the cumulative risk of DP for patients and comparators from index date (defined as 1 year after diagnosis) with competing events (transplantation or relapse, death, retirement pension, or early retirement pension). Differences in cumulative incidences were calculated using Gray's test. RTW was calculated as proportions one, three, and five years after the index date for patients holding a job before diagnosis.

Results

A total of 154 patients with ALL and 770 matched comparators were included. The 5-year cumulative risk of DP was increased fivefold for patients with ALL compared with the general population. RTW was 41.7%, 65.7%, and 60.7% one, three, and five years after the index date, respectively.

Conclusion

The risk of DP in patients with ALL increased significantly compared with the general population. Five years after the index date, RTW was 60.7% for patients with ALL.

Venetoclax-based therapy for relapsed or refractory acute myeloid leukaemia following intensive induction chemotherapy

BACKGROUND

The treatment of relapsed or refractory (R/R) acute myeloid leukaemia (AML) remains challenging and outcomes extremely poor. The introduction of venetoclax has transformed the treatment of AML and emerging data suggest that venetoclax-based therapy may enforce salvage treatment.

MATERIALS AND METHODS

In this nationwide Danish retrospective study, we analysed treatment outcomes of venetoclax-based salvage treatment for R/R AML between 2019 and 2022. Only venetoclax-naive patients who had previously received treatment with intensive chemotherapy therapy were included.

RESULTS

The cohort consisted of 43 R/R patients with a median age of 57 years. Nine (20.9%) were primary refractory and 34 (79.1%) patients had relapsed, including 21 after previous allogeneic stem cell transplantation. The overall response rate was 76.2% including 61.9% with composite complete remission (CRc: CR + CRi). Among CRc-responders with information on measurable residual disease (MRD), 8/13 (61.5%) obtained an MRD-negativity response. The overall survival was 9.3 months for all patients with an estimated 1-year overall survival of 34%. For CRc-responders the median overall survival was 13.3 months, and the median relapse-free survival was 12.8 months.

CONCLUSION

Venetoclax-based salvage treatment for R/R AML produced high response rates; however, for most patients the response was of limited duration. This study is limited by an observational design and prone to selection bias.

LEP promoter methylation in the initiation and progression of clonal cytopenia of undetermined significance and myelodysplastic syndrome

BACKGROUND

Idiopathic non-clonal cytopenia (ICUS) and clonal cytopenia (CCUS) are common in the elderly population. While these entities have similar clinical presentations with peripheral blood cytopenia and less than 10% bone marrow dysplasia, their malignant potential is different and the biological relationship between these disorders and myeloid neoplasms such as myelodysplastic syndrome (MDS) is not fully understood. Aberrant DNA methylation has previously been described to play a vital role in MDS and acute myeloid leukemia (AML) pathogenesis. In addition, obesity confers a poorer prognosis in MDS with inferior overall survival and a higher rate of AML transformation. In this study, we measured DNA methylation of the promoter for the obesity-regulated gene LEP, encoding leptin, in hematopoietic cells from ICUS, CCUS and MDS patients and healthy controls. We investigated whether LEP promoter methylation is an early event in the development of myeloid neoplasms and whether it is associated with clinical outcome.

RESULTS

We found that blood cells of patients with ICUS, CCUS and MDS all have a significantly hypermethylated LEP promoter compared to healthy controls and that LEP hypermethylation is associated with anemia, increased bone marrow blast percentage, and lower plasma leptin levels. MDS patients with a high LEP promoter methylation have a higher risk of progression, shorter progression-free survival, and inferior overall survival. Furthermore, LEP promoter methylation was an independent risk factor for the progression of MDS in a multivariate Cox regression analysis.

CONCLUSION

In conclusion, hypermethylation of the LEP promoter is an early and frequent event in myeloid neoplasms and is associated with a worse prognosis.

Impact of U2AF1 mutations on circular RNA expression in myelodysplastic neoplasms

Mutations in U2AF1 are relatively common in myelodysplastic neoplasms (MDS) and are associated with an inferior prognosis, but the molecular mechanisms underlying this are not fully elucidated. Circular RNAs (circRNAs) have been implicated in cancer, but it is unknown how mutations in splicing factors may impact on circRNA biogenesis. Here, we used RNA-sequencing to investigate the effects of U2AF1 mutations on circRNA expression in K562 cells with a doxycycline-inducible U2AF1^S34 mutation, in a mouse model with a doxycycline-inducible U2AF1^S34 mutation, and in FACS-sorted CD34+ bone marrow cells from MDS patients with either U2AF1^S34 or U2AF1^Q157 mutations. In all contexts, we found an increase in global circRNA levels in the U2AF1-mutated setting, which was independent of expression changes in the cognate linear host genes. In patients, the U2AF1^S34 and U2AF1^Q157 mutations were both associated with an overall increased expression of circRNAs. circRNAs generated by a non-Alu-mediated mechanism generally showed the largest increase in expression levels. Several well-described cancer-associated circRNAs, including circZNF609 and circCSNK1G3, were upregulated in MDS patients with U2AF1 mutations compared to U2AF1-wildtype MDS controls. In conclusion, high circRNA expression is observed in association with U2AF1 mutations in three biological systems, presenting an interesting possibility for biomarker and therapeutic investigation.

Effects of chemotherapy dose reductions in overweight patients with acute myeloid leukaemia: A Danish nationwide cohort study

Overweight patients with cancer are frequently reduced in chemotherapy dose due to toxicity concerns, although previous studies have indicated that dose reduction (DR) of overweight patients results in comparable toxicity but may compromise overall survival (OS). Current evidence regarding DR in patients with acute myeloid leukaemia (AML) is limited. To investigate the association between DR and outcome among overweight patients with AML we analysed a Danish nationwide cohort of overweight adult AML patients treated with remission induction chemotherapy. Among 536 patients identified, 10.1% were categorized as DR defined as 95% or less of full body surface area (BSA)-based dose. Risk factors for DR were high body mass index (BMI) and BSA, therapy-related AML and favourable cytogenetics. No significant differences were observed for rates of complete remission (CR), 30- and 90-day mortality between DR and non-DR patients. Furthermore, DR did not affect median relapse-free survival (RFS) [DR, 14.5 (95% confidence interval, 9.0-41.7) months; non-DR, 15.0 (12.3-19.3)] with an adjusted difference in five-year restricted mean survival time (Δ5y-RMST) of 0.2 (-8.4 to 8.8) months nor median OS (DR, 17.0 [11.9 to 45.5] months; non-DR, 17.5 [14.8 to 20.5]) with an adjusted Δ5y-RMST of 0.8 (-5.7 to 7.3) months. In conclusion, we found no statistically significant association between DR and outcomes among overweight patients with AML. However, we acknowledge the limited sample size and encourage further studies in this important subject.

The value of next-generation sequencing in routine diagnostics and management of patients with cytopenia

INTRODUCTION

We performed a single-center study of real-world health data to investigate the direct clinical consequence of targeted next-generation sequencing (NGS) results integrated in the clinicopathological evaluation of patients with cytopenia suspected of myelodysplastic syndrome (MDS).

METHODS

The study included 87 newly referred patients, who had a bone marrow examination, which included targeted NGS analysis. NGS was requested at the discretion of either examining pathologist or hematologist. Data were collected retrospectively from patient files including pathology reports with integrated NGS results.

RESULTS

The NGS results had a diagnostic impact in 67 cases (77%) when combining both histopathological and final clinical evaluation and provided prognostic value in 19 cases (22%). NGS supported a confident or tentative histopathological diagnosis in 52 cases (60%). Twenty cases (23%) had a final diagnosis of either Clonal Cytopenia of Undetermined Significance (CCUS) or Idiopathic Cytopenia of Undetermined Significance (ICUS). In 4 cases, NGS results affected the choice of principal treatment strategy, including considerations of allotransplantation. Twenty-one patients (24%) could be discharged to primary care physician.

CONCLUSION

In a multidisciplinary clinicopathological real-world setting, NGS analysis of bone marrow samples from selected patients contributed substantially to the diagnostic evaluation and management of patients with cytopenia suspected of MDS. Consequently, we have now included NGS analysis in most routine bone marrow examinations from patients with MDS or unexplained cytopenia.

Psychotropic Drug Use in Acute Myeloid Leukaemia (AML) and Myelodysplastic Syndrome (MDS): A Danish Nationwide Matched Cohort Study of 2404 AML and 1307 MDS Patients

Introduction

The diagnosis of a life-threatening disease can lead to depression and anxiety resulting in pharmacological treatment. However, use of psychotropic drugs (antidepressants, anxiolytics, and antipsychotics) in acute myeloid leukaemia (AML) and myelodysplastic syndrome (MDS) is undetermined.

Methods

Prescription of psychotropic drugs in Danish AML and MDS patients was compared to a cohort matched on age, sex, and country of origin from the Danish background population using national population-based registries.

Results

In total, 2404 AML patients (median age 69 years) and 1307 MDS patients (median age 75 years) were included and each matched to five comparators from the background population. Two-year cumulative incidences showed that AML (20.6%) and MDS (21.2%) patients had a high risk of redemption of a psychotropic drug prescription compared to the background population (7.0% and 7.9%). High age, low educational level, and Charlson Comorbidity Index score ≥1 was associated with a higher risk in AML and MDS patients. Furthermore, non-curative treatment intent and performance status in AML patients, and high risk MDS were associated with elevated risk of psychotropic drug prescription.

Conclusion

In conclusion, diagnoses of AML and MDS were associated with a higher rate of psychotropic drugs prescription compared to the background population.

A national Danish proof of concept on feasibility and safety of home -based intensive chemotherapy in patients with acute myeloid leukemia

Technological advances have made it possible to offer home-based chemotherapy to patients without health care professionals being present. Prior studies on effects of home-based treatment lack inclusion of patients with hematologic malignancies. We present data from a multicenter single-arm feasibility and safety study of home-based intensive chemotherapy in patients with newly diagnosed acute myeloid leukemia and their quality of life and psychological wellbeing. This national study included patients from six sites in Denmark who received intensive chemotherapy on programmed CADD Solis infusion pumps through a central venous catheter and were also managed as outpatients during treatment-induced pancytopenia. Data are presented from 104 patients, receiving 272 treatments with 1.096 (mean 4.57, SD 3.0) home infusion days out of 1.644 treatment days (67 %). Sixty-two of 168 (36.9 %) reinduction and consolidation treatment cycles ensuing pancytopenia phases were solely handled in the outpatient clinic. Patients reported high satisfaction with home-based treatment, which had a positive influence on their ability to be involved in their treatment and be socially and physically active. No unexpected events occurred during the intervention. Overall, patients improved in all quality of life outcomes over time. Home-based intensive chemotherapy treatment was feasible and safe in this population. ClinicalTrials.gov identifier: NCT04904211.

Improved Variant Detection in Clinical Myeloid NGS Testing by Supplementing a Commercial Myeloid NGS Assay with Custom or Extended Data Filtering and Accessory Fragment Analysis

BACKGROUND

Commercial myeloid next-generation sequencing (NGS) panels may facilitate uniform generation of raw data between laboratories. However, different strategies for data filtering and variant annotation may contribute to differences in variant detection and reporting. Here, we present how custom data filtering or the use of Oncomine extended data filtering improve detection of clinically relevant mutations with the Oncomine Myeloid Research Assay.

METHODS

The study included all patient samples (n = 264) analyzed during the first-year, single-site, clinical use of the Ion Torrent Oncomine Myeloid Research Assay. In data analysis, the default analysis filter was supplemented with our own data filtering algorithm in order to detect additional clinically relevant mutations. In addition, we developed a sensitive supplementary test for the ASXL1 c.1934dupG p.Gly646fs mutation by fragment analysis.

RESULTS

Using our custom filter chain, we found 96 different reportable variants that were not detected by the default filter chain. Twenty-six of these were classified as variants of strong or potential clinical significance (tier I/tier II variants), and the custom filtering discovered otherwise undetected tier I/tier II variants in 25 of 132 patients with clinically relevant mutations (19%). The remaining 70 variants not detected by the default filter chain were classified as variants of unknown significance. Among these were several unique variants with possible pathogenic potential judged by bioinformatic predictions. The recently launched Oncomine 5.14 extended filter algorithm detects most but not all of the tier I/tier II variants that were not detected by the default filter. The supplementary fragment analysis for the ASXL1 c.1934dupG p.Gly646fs confidently detected a variant allele frequency of down to 4.8% (SD 0.83%). The assay also detected the ASXL1 c.1900_1922del23 mutation.

CONCLUSION

Detection of clinically relevant variants with the Oncomine Myeloid Research NGS assay can be significantly improved by supplementing the default filter chain with custom data filtering or the recently launched Oncomine 5.14 extended filter algorithm. Our accessory fragment analysis facilitates easy testing for frequent ASXL1 mutations that are poorly or not covered by the NGS assay.

Therapeutic Cancer Vaccination With a Peptide Derived From the Calreticulin Exon 9 Mutations Induces Strong Cellular Immune Responses in Patients With CALR-Mutant Chronic Myeloproliferative Neoplasms

Background

The calreticulin (CALR) exon 9 mutations that are identified in 20% of patients with Philadelphia chromosome negative chronic myeloproliferative neoplasms (MPN) generate immunogenic antigens. Thus, therapeutic cancer vaccination against mutant CALR could be a new treatment modality in CALR-mutant MPN.

Methods

The safety and efficacy of vaccination with the peptide CALRLong36 derived from the CALR exon 9 mutations was tested in a phase I clinical vaccination trial with montanide as adjuvant. Ten patients with CALRmut MPN were included in the trial and received 15 vaccines over the course of one year. The primary end point was evaluation of safety and toxicity of the vaccine. Secondary endpoint was assessment of the immune response to the vaccination epitope (www.clinicaltrials.gov identifier NCT03566446).

Results

Patients had a median age of 59.5 years and a median disease duration of 6.5 years. All patients received the intended 15 vaccines, and the vaccines were deemed safe and tolerable as only two grade three AE were detected, and none of these were considered to be related to the vaccine. A decline in platelet counts relative to the platelets counts at baseline was detected during the first 100 days, however this did not translate into neither a clinical nor a molecular response in any of the patients. Immunomonitoring revealed that four of 10 patients had an in vitro interferon (IFN)-γ ELISPOT response to the CALRLong36 peptide at baseline, and four additional patients displayed a response in ELISPOT upon receiving three or more vaccines. The amplitude of the immune response increased during the entire vaccination schedule for patients with essential thrombocythemia. In contrast, the immune response in patients with primary myelofibrosis did not increase after three vaccines.

Conclusion

Therapeutic cancer vaccination with peptide vaccines derived from mutant CALR with montanide as an adjuvant, is safe and tolerable. The vaccines did not induce any clinical responses. However, the majority of patients displayed a marked T-cell response to the vaccine upon completion of the trial. This suggests that vaccines directed against mutant CALR may be used with other cancer therapeutic modalities to enhance the anti-tumor immune response.

Temporal changes in survival among adult patients with acute myeloid leukaemia in the period 2000-2016: a Danish population-based study

In the present study, we quantify the progress in overall survival (OS) during the period 2000-2016 among Danish patients with acute myeloid leukaemia (AML). This population-based study, including 3820 adult patients with AML, demonstrates a significantly improved OS over time with the 2-year age-standardised OS increasing from 22% in 2002 to 31% in 2016. The improvement in OS was exclusively seen in patients with AML aged ≥50 years, with absolute improvements in 2-year OS from 2002 to 2016 of ≥10% among patients aged 50-75 years and a small absolute increase in those aged >75 years.

The prognostic effect of smoking status on intensively treated acute myeloid leukaemia - A Danish nationwide cohort study

With rising life expectancy, the importance of patient-related prognostic factors and how to integrate such data into clinical decision-making becomes increasingly important. The aim of this study was to evaluate the prognostic impact of smoking status in patients with acute myeloid leukaemia (AML) treated with intensive chemotherapy. We conducted a nationwide cohort study based on data obtained from the Danish National Leukaemia Registry (DNLR). The study comprised Danish patients aged 18-75 years, diagnosed with AML between 1 January 2000 and 31 December 2012. Medical records were reviewed and data on smoking status were collected. A total of 1040 patients (median age 59 years) were included, and 602 patients (58·9%) were categorised as ever-smokers and the remaining as never-smokers. Kaplan-Meier survival estimates revealed that ever-smokers had a significant shorter median overall survival (OS) at 17·2 months [95% CI (14·9;19·1)] compared to never-smokers at 24·5 months (95% CI [19·2;30·7]). Multivariate analysis revealed smoking status as a significant prognostic factor for inferior OS with a hazard ratio (HR) of 1·22 [95% CI (1·04;1·44)]. In conclusion, smoking status was found to be associated with inferior OS in intensively treated AML patients.

NSAID consumption and risk of acute myeloid leukemia: a national population-based case-control study

Background

Most cases of acute leukemia arise without identifiable risk factors. Studies investigating the impact of autoimmune diseases and infections on leukemogenesis have revealed conflicting results. If inflammation increases the risk of acute myeloid leukemia (AML), nonsteroidal anti-inflammatory drug (NSAID) use may decrease the risk of leukemia.

Methods

We conducted a case-control study of 3,053 patients with AML diagnosed between 2000 and 2013, who were registered in the Danish National Acute Leukemia Registry, and 30,530 population controls matched on sex and age. We identified prescriptions through the Danish National Health Service Prescription Database. We used conditional logistic regression analysis to compute ORs associating AML with NSAID use overall, in patients with inflammatory diseases, and for specific AML subtypes (de novo AML, AML related to previous hematological disease, ie, secondary AML [sAML], or therapy-related AML [tAML; exposed to previous cytotoxic therapy]).

Results

Overall, NSAID use was not associated with a lower risk of AML (OR 1.1, 95% CI=1.0-1.2), de novo AML (OR 1.0, 95% CI=0.9-1.1), and sAML/tAML (OR 1.3, 95% CI=1.1-1.5). In addition, in patients with known inflammatory diseases, NSAIDs did not affect AML risk (OR 0.9, 95% CI=0.5-1.6). Number of prescriptions, type of NSAID, age, or sex did not influence the results.

Conclusion

In line with our recent findings that showed no association between autoimmune diseases and infections and de novo AML, NSAID use was not found to reduce the risk of AML.

Autoimmune diseases, infections, use of antibiotics and the risk of acute myeloid leukaemia: a national population-based case-control study

Previous studies reported increased risk of acute myeloid leukaemia (AML) in individuals with inflammatory conditions. However, it is unclear whether this association is explained by preceding cytotoxic therapy or haematological diseases. We conducted a nationwide case-control study that included 3053 AML patients, diagnosed in Denmark between 2000 and 2013, and 30 530 sex- and age-matched population controls. We retrieved information on autoimmune disease, infections, and use of antibiotics and computed odds ratios for AML (conditional logistic regression). Results were stratified by AML type, sex, and age. Autoimmune diseases were associated with an overall increased risk of AML {odds ratio [OR] 1·3 [95% confidence interval (CI) = 1·1-1·5]}. However, the risk was confined to patients with previous haematological disease or cytotoxic therapy exposure [secondary/therapy-related AML (sAML/tAML0) OR 2·0 (95% CI = 1·6-2·6)] and not de novo AML [OR 1·1 (95% CI = 0·9-1·3)]. Similarly, any prior infection requiring hospitalization was associated with a higher risk of AML [OR 1·3 (95% CI = 1·1-1·4)]. Again, this association was evident for sAML/tAML [OR 1·8 (95% CI = 1·5-2·2)], and not de novo AML [OR 1·1 (95% CI = 1·0-1·2)]. In conclusion, autoimmune diseases and infections were associated with an increased AML risk only in subjects with prior haematological disease and/or cytotoxic treatment. These observations suggest, that inflammation plays - if any - a minor role for the development of de novo AML.

Evaluation of clinical trial eligibility and prognostic indices in a population-based cohort of systemic peripheral T-cell lymphomas from the Danish Lymphoma Registry

Clinical trials (CTs) are needed to improve the outcome for peripheral T-cell lymphomas (PTCL), and accrual into CTs is one of the main recommendations in international treatment guidelines. The use of risk-adapted strategies has been suggested as a way to optimize treatment outcome in PTCL. The aim of the present study was to evaluate CT eligibility and selected prognostic indices in a population-based PTCL cohort of 481 PTCL patients identified from the Danish Lymphoma Registry in the period 2000-2010. According to five predefined parameters (age, performance status, P-creatinine, P-ALAT and measurable tumour lesion), patients were subdivided into four groups: 'younger fit', 'elderly fit', 'frail' and 'not CT eligible'. International prognostic index (IPI), prognostic index for T-cell lymphoma (PIT) and anaplastic lymphoma kinase (ALK) protein expression were tested at subtype-specific level. Overall, 41% of the patients were considered eligible for interventional CTs implicating curatively intended multiagent chemotherapy, including, if considered appropriate, consolidating stem cell transplantation (SCT), as part of the upfront management strategy. Moreover, 28% was elderly fit and eligible for interventional CT, including those with SCT as part of the trial design. Approximately 7% were defined as 'too frail' for aggressive treatment schedules, whereas 24% were deemed not to be eligible for any CT. Both overall and progression-free survivals were effectively predicted by IPI and PIT (p < 0.001). ALK-positive anaplastic large cell lymphoma patients were significantly younger (median age 40 vs. 62, p < 0.001) and had a better outcome than their ALK-negative counterparts (p < 0.001). However, ALK expression lost its prognostic significance when adjusting for age. In a population-based cohort of adult Caucasian PTCL patients, approximately half were eligible for multiagent chemotherapy with or without consolidating SCT. Both IPI and PIT are useful prognostic indices in all 'primary nodal' PTCL entities. The prognostic value of ALK protein expression in anaplastic large cell lymphoma is significantly downsized when adjusting for age.

Supraclavicular recurrence after early breast cancer: a curable condition?

The prognosis of ipsilateral supraclavicular lymph node recurrence after early breast cancer appears to be worse than for other loco-regional recurrences, but better than for distant metastases. The purpose of the present study was to investigate the relationship between different types of salvage treatment and primary patient characteristics, treatment response, and survival after supraclavicular recurrence (SR) in a large patient population. From the Danish Breast Cancer Cooperative Group treatment database 1977-2003, 305 patients were identified with SR without distant disease as site of first recurrence. Salvage treatment types as well as other factors were related to response and survival. The median follow-up time for progression after SR was 25 months. Complete remission was 76% among patients receiving excision surgery, 67% with combined loco-regional and systemic therapy, and 48% with systemic therapy alone. Median progression-free survival (PFS) and overall survival was 18 and 29 months, respectively. The 5-year PFS probability was 15%. In univariate analysis, combination salvage therapy, negative nodal status and low malignancy grade were related to longer PFS. In multivariate analysis, salvage therapy and malignancy grade remained independent factors for survival. In conclusion, the prognosis of SR is generally poor. However, it appears to be a curable condition. An independent marker of improved outcome is local and systemic combination salvage treatment, which can be considered.

Rituximab in chronic cold agglutinin disease: a prospective study of 20 patients

Chronic cold agglutinin disease (CAD) is an acquired autoimmune hemolytic anemia. Previous therapeutic modalities, including alkylating cytostatics, interferon and prednisolone, have been disappointing. However, several case reports and small-scaled studies have demonstrated promising results after treatment with rituximab. We performed a phase II multicentre trial to investigate the effect of rituximab in CAD, including 20 patients studied from October 2002 until April 2003. Thirteen patients had idiopathic CAD and seven patients had CAD associated with a malignant B-cell lymphoproliferative disease. Rituximab was given in doses of 375 mg/m(2) at days 1, 8, 15 and 22. Sixteen patients were followed up for at least 48 weeks. Four patients were excluded after 8, 16, 23 and 28 weeks for reasons unrelated to CAD. Nine patients (45%) responded to the treatment, one with complete response (CR), and eight with partial response. Eight patients relapsed, one patient was still in remission at the end of follow-up. There were no serious rituximab-related side-effects. Our study confirms previous findings of a favourable effect of rituximab in patients with CAD. However, few patients will obtain CR and, in most patients, the effect will be transient.

Hepatitis C infection and risk of malignant lymphoma

The association between hepatitis C virus (HCV) infection and risk of malignant lymphoma remains controversial, perhaps due to small-sized studies and low prevalence of HCV in the general population. On the basis of a large Danish-Swedish population-based case-control study, 2,819 lymphoma patients and 1,856 controls of second-generation Danish-Swedish origin were screened for HCV infection using an enzyme-linked immunosorbent assay and a confirming recombinant immunoblot assay (RIBA) test. Positive samples were tested with real-time PCR for the presence of HCV RNA. The association between HCV infection and risk of malignant lymphoma was assessed by logistic regression. When intermediate RIBA test results were interpreted as positive, anti-HCV antibody positivity was associated with a nonsignificant increased risk of non-Hodgkin lymphoma (NHL) overall (odds ratio (OR) = 2.2; 95% confidence interval (CI) 0.9-5.3; n = 20 cases), of B-cell lymphomas combined (OR = 2.4 [1.0-5.8]; n = 20) and of lymphoplasmacytic lymphoma (OR = 5.2 [1.0-26.4]; n = 2). No patients with T-cell or Hodgkin lymphoma were HCV-positive. A more conservative definition of HCV positivity (disregarding intermediate RIBA results) resulted in an OR = 1.6 (0.3-8.5; n = 5) for NHL overall. When the definition was further restricted to require HCV RNA positivity, OR was 1.7 (0.2-16.2; n = 3) for NHL overall. Our findings from a population with a low prevalence of HCV suggest a positive association between HCV and risk of NHL, in particular of B-cell origin.

Cigarette smoking and risk of Hodgkin lymphoma: a population-based case-control study

BACKGROUND

Studies have inconsistently reported an association between tobacco smoking and Hodgkin lymphoma (HL) risk. The conflicting finding may reflect etiologic heterogeneity between HL subtypes, warranting further characterization of the relationship.

METHODS

We collected information on tobacco-smoking habits in 586 classic HL cases and 3,187 population controls in a Danish-Swedish case-control study. HL EBV status was established for 499 cases by standard techniques. Odds ratios (OR) for an association with cigarette smoking were calculated by logistic regression for HL overall and stratified by age, sex, major histology subtypes, and tumor EBV status, adjusting for known confounders.

RESULTS

Compared with never smokers, current cigarette smokers were at an increased overall HL risk [adjusted OR, 1.57; 95% confidence interval (95% CI), 1.22-2.03]. The association was strongest for EBV-positive HL (adjusted OR, 2.36; 95% CI, 1.51-3.71), but also applied to EBV-negative HL (adjusted OR, 1.43; 95% CI, 1.05-1.97; P(homogeneity EBV-pos) versus P(homogeneity EBV-neg) = 0.04). The association did not vary appreciably by age, sex, or histologic subtype, the apparent EBV-related difference present in all strata. There was no evidence of a dose-response pattern, whether by age at smoking initiation, daily cigarette consumption, number of years smoking, or cumulative number of cigarettes smoked. Similar results were obtained in analyses using non-HL patients (n = 3,055) participating in the founding study as comparison group.

CONCLUSION

The observed association between cigarette smoking and HL risk is consistent with previous findings and biologically credible. Although not easily dismissed as an artifact, the limited evidence of a dose-response pattern renders the overall evidence of causality weak.

Atopy and Risk of Non-Hodgkin Lymphoma

BACKGROUND

A possible connection between allergy and cancer has been suspected, but allergy-related conditions or atopy have been inconsistently associated with reduced risks of non-Hodgkin lymphoma. We investigated this association in a population-based case-control study and in a prospective study with prediagnostic blood specimens.

METHODS

We carried out a population-based study of 3055 case patients with non-Hodgkin lymphoma and 3187 control subjects in Denmark and Sweden, including questionnaire information on allergy and blood specimens, and a nested case-control study within a prospective cohort of more than 400,000 Finnish women. In the second study, serum specimens from the 198 case patients who developed non-Hodgkin lymphoma within a median of 8.9 years after the blood was drawn were matched with serum specimens from 594 control subjects. In both studies, laboratory-based evidence of allergy (atopy) was determined in serum on the basis of specific IgE reactivity to common inhalant allergens. Dissemination of disease was classified by the Ann Arbor system. Odds ratios (ORs) with 95% confidence intervals (CIs) were calculated by logistic regression.

RESULTS

In the first study, ever having hay fever, but not other allergic conditions, was associated with a reduced risk of non-Hodgkin lymphoma. In particular, subjects with specific IgE reactivity in serum had a 32% (95% CI = 20% to 42%) lower risk of overall non-Hodgkin lymphoma than those without such reactivity. However, among case patients, dissemination of the disease was strongly inversely associated with specific IgE reactivity. In the second (i.e., prospective) study, no association was found between non-Hodgkin lymphoma and specific IgE reactivity, except possibly immediately before a diagnosis of non-Hodgkin lymphoma (> or = 10 years before diagnosis, OR = 1.00, 95% CI = 0.48 to 2.09; 5-9 years before, OR = 0.95, 95% CI = 0.50 to 1.84; 1-4 years before, OR = 0.33, 95% CI = 0.11 to 1.02; and < 1 year before, OR = 0.27, 95% CI = 0.03 to 2.31).

CONCLUSION

Allergy may not be causally associated with the risk of non-Hodgkin lymphoma. The inverse association observed in some case-control studies may arise because non-Hodgkin lymphoma suppresses the immunologic response to allergens.

Risk of second cancer after chronic lymphocytic leukemia

Smoking is not considered a risk factor for chronic lymphocytic leukemia (CLL) yet increased lung cancer risk has been reported for these patients. Little data exist on the temporal variation in lung cancer risk after CLL, or its histological composition. We investigated the occurrence of second cancers in a large cohort of CLL patients with particular emphasis on lung cancer and its major subtypes. We followed all patients diagnosed with CLL in Denmark in the period 1943-2003 (n = 12,373) for the occurrence of second cancers. The relative risk was expressed as the standardized incidence ratio (SIR), i.e. the ratio of observed to expected number of cancers, based on incidence rates for the Danish population. During follow-up 1,105 cancers occurred among the CLL patients (SIR = 1.59 (95% CI 1.50-1.69)). SIR for all cancers combined remained elevated more than 10 years after CLL (SIR = 1.80 (1.56-2.08)). Lung cancer occurred in 141 patients (SIR = 1.61 (1.37-1.90)). The relative risk of lung cancer did not vary by gender, or time of follow-up, but was higher in younger (SIR(<60 years) = 2.22 (1.62-3.06)) than in older (SIR(70-79 years) = 1.21 (0.88-1.68)) age-groups. Elevated risks were observed for adenocarcinoma (SIR = 2.20 (1.57-3.08)) and squamous cell carcinoma (SIR = 1.52 (1.06-2.17)) of the lung. We speculate that shared genetic risk factors may explain the accumulation of lung and other cancers in CLL patients.

Variation in DNA repair genes ERCC2, XRCC1, and XRCC3 and risk of follicular lymphoma

The reasons for the positive association between skin cancer and non-Hodgkin's lymphoma are not known but may be due to common susceptibility involving suboptimal DNA repair. Therefore, we investigated selected polymorphisms and haplotypes in three DNA repair genes, previously associated with skin cancer and DNA repair capacity, in risk of follicular lymphoma, including possible gene interaction with cigarette smoking and sun exposure. We genotyped 19 single nucleotide polymorphisms (SNP) in the ERCC2, XRCC1, and XRCC3 genes in 430 follicular lymphoma patients and 605 controls within a population-based case-control study in Denmark and Sweden. Odds ratios (OR) and 95% confidence intervals (95% CI) were calculated using unconditional logistic regression and haplotype associations were assessed with a global score test. We observed no associations between variation in the ERCC2 and XRCC1 genes and follicular lymphoma risk. In XRCC3, increased risk of follicular lymphoma was suggested for rare homozygotes of three SNPs [Rs3212024: OR, 1.8 (95% CI, 1.1-2.8); Rs3212038: OR, 1.5 (95% CI, 1.0-2.4); Rs3212090: OR, 1.5 (95% CI, 1.0-2.5)]. These results were strengthened in current cigarette smokers. However, evidence of differences in XRCC3 haplotype distributions between follicular lymphoma cases and controls was weak, both overall and in current smokers. We conclude that polymorphic variation in the XRCC3 gene, but not in ERCC2 or XRCC1, may be of importance for susceptibility to follicular lymphoma, perhaps primarily in current smokers. The link between skin cancer and follicular lymphoma is unlikely to be mediated through common variation in the studied DNA repair gene polymorphisms.

Medication use and risk of non-Hodgkin's lymphoma

Conflicting results from previous epidemiologic studies shed little light on whether medication use is associated with risk of non-Hodgkin's lymphoma (NHL). To investigate this question, the authors conducted a population-based case-control study in Denmark and Sweden from 1999 to 2002, including 3,055 incident NHL cases and 3,187 controls. Participants reported their past use of medications and history of particular medical conditions. Unconditional logistic regression was used to estimate multivariate odds ratios and 95% confidence intervals for the associations between medication use and risk of NHL; all statistical tests were two sided. Use of antibiotics more than 10 times during adulthood was positively associated with risk of NHL and most major NHL subtypes; when users were compared with nonusers, the odds ratio for NHL was 1.8 (95% confidence interval: 1.4, 2.3); p(trend) for total antibiotic use <0.001. In addition, high cumulative use of nonsteroidal anti-inflammatory drugs was marginally associated with elevated NHL risk. Other medications evaluated were not associated with risk of NHL or its most common subtypes. Findings suggest that inflammation, infections, susceptibility to infections, and/or use of antibiotics or nonsteroidal anti-inflammatory drugs to treat these conditions may increase the risk of NHL. However, most of the medications examined were not associated with NHL risk.

Cigarette smoking and risk of non-Hodgkin's lymphoma--a population-based case-control study

BACKGROUND

Epidemiologic evidence of an association between tobacco smoking and non-Hodgkin's lymphoma has been conflicting. This may reflect that non-Hodgkin's lymphoma comprises several distinct disease entities with different etiologies, as some studies have indicated an association between smoking and follicular lymphoma.

OBJECTIVE

To investigate the association between cigarette smoking and non-Hodgkin's lymphoma risk, overall and by subtype.

METHODS

As part of a nationwide Danish-Swedish population-based case-control study, we interviewed 3,055 incident non-Hodgkin's lymphoma patients and 3,187 population controls. All lymphomas were uniformly classified according to the WHO classification. We used unconditional logistic regression to estimate adjusted odds ratios (OR) and 95% confidence intervals (95% CI) for the association between cigarette smoking and risk of non-Hodgkin's lymphoma.

RESULTS

Cigarette smoking was not associated with the risk of non-Hodgkin's lymphoma overall (OR, 0.97; 95% CI, 0.87-1.08) nor with the major subgroups such as diffuse large B-cell lymphoma (OR, 0.94; 95% CI, 0.79-1.10), chronic lymphocytic leukemia (OR, 0.86; 95% CI, 0.72-1.02), or follicular lymphoma (OR, 1.03; 95% CI, 0.85-1.24). Female smokers were at a marginally increased risk of follicular lymphoma (OR, 1.41; 95% CI, 1.04-1.92). Men who had ever smoked had a significantly increased risk of T-cell lymphoma (OR, 1.67; 95% CI, 1.11-2.51). No dose-response association with cigarette smoking could be established for any lymphoma subgroup.

CONCLUSION

We found little evidence of an association between cigarette smoking and non-Hodgkin's lymphoma risk overall. Although increased risks of follicular lymphoma in female smokers and of T-cell lymphoma in male smokers were suggested, no dose-response relationship was observed, leaving limited support for causality.