Survival outcomes and healthcare utilization between immigrant patients and Danish-born patients with hematological cancers: a Danish population-based study.

Overall survival (OS) for patients with a hematological cancer may differ between immigrant and Danish-born patients due to disparities in socioeconomic status, health literacy, and language proficiency. This cohort study aimed to investigate survival and hospitalization according to immigrant status while controlling for confounders. Patients with newly diagnosed hematological cancer in 2000-2020 were identified in the Danish nationwide hematological registers and stratified into Danish-born, Western, and non-Western patients. Patients were followed from diagnosis until death, 31st December 2021, or emigration, whichever came first. Crude OS, standardized OS, and 5-years OS differences were computed using flexible parametric models and hazard ratios using Cox regression. Number of hospitalization days in the year before and after diagnosis, respectively, were calculated using Poisson regression. A total of 2,241 immigrants and 41,519 Danish-born patients with a hematological cancer were included. Standardized 5-years OS was similar between groups with 58% (95% confidence interval 57-58%) for Danish-born patients, 57% (55-60%) for Western, and 56% (53-58%) for non-Western immigrant patients. Subgroup analyses identified OS differences in selected subgroups. Non-Western immigrant patients had 1.3 (0.5-2.1) more hospitalization days in the year before diagnosis and an adjusted incidence rate ratio of hospitalization days of 1.14 (1.13-1.15) in the year after diagnosis compared with Danish-born patients. In conclusion, there were no overall differences in survival when comparing immigrant patients to Danish-born patients after controlling for relevant confounders. Healthcare utilization was slightly higher among non-Western immigrant patients before and after diagnosis, but differences were small on an individual patient level.

The impact of trial inclusion criteria on outcomes in DLBCL patients treated with R-CHOP in the first line: a Danish nationwide study.

Up to 50% of diffuse large B-cell lymphoma (DLBCL) patients are ineligible for participation in clinical trials. Ineligible patients have inferior outcomes, but less is known about the impact of commonly used organ-function-based inclusion criteria on drug efficacy estimates. Data on DLBCL patients treated with CHOP+/-rituximab were retrieved from the Danish Lymphoma Registry. Trial inclusion criteria were extracted from four international DLBCL trials (REMoDL-B, GOYA, POLARIX, and HOVON-84). Differences in overall survival (OS) and 5-year restricted mean survival differences (5 y-RMSDs) between trial eligible and ineligible patients were computed. The effectiveness of adding rituximab to CHOP was quantified by the 5 y-RMSD between CHOP and R-CHOP-treated patients and the impact of individual trial criteria on estimated effectiveness was quantified by Shapley-values. In total, 4,083 R-CHOP-treated and 890 CHOP-treated DLBCL patients were included. Across the trials, 18.6-29.3% of the included R-CHOP-treated patients were deemed ineligible for trial based on organ function and performance status alone. Ineligible patients had significantly worse survival, with adjusted absolute differences in 5-year OS of 9-15%. The impact of individual criteria on the estimated effectiveness of adding rituximab to CHOP was small (Shapley-value range, -2.74-0.31). Using a smaller set of criteria derived from a data-driven approach, the number of eligible patients increased by 16-38% and the 5 y-RMSD increased by 0.7-3.1 months. In conclusion, OS among trial ineligible DLBCL patients is inferior as expected, but relaxing trial criteria would have increased the number of trial participants without making major changes in estimated efficacy for a hypothetical CHOP versus R-CHOP trial. This does not necessarily imply that trial findings based on selected patients are unreliable, as the estimated effectiveness of adding rituximab to CHOP was only slightly affected by omitting selected inclusion criteria.