Abstract: Aims How and why lymphoma cells home to the central nervous system and vitreoretinal compartment in primary diffuse large B-cell lymphoma of the central nervous system remain unknown. Our aim was to create an in vivo model to study lymphoma cell tropism to the central nervous system. Methods We established a patient-derived central nervous system lymphoma xenograft mouse model and characterised xenografts derived from four primary and four secondary central nervous system lymphoma patients using immunohistochemistry, flow cytometry and nucleic acid sequencing technology. In reimplantation experiments, we analysed dissemination patterns of orthotopic and heterotopic xenografts and performed RNA sequencing of different involved organs to detect differences at the transcriptome level. Results We found that xenografted primary central nervous system lymphoma cells home to the central nervous system and eye after intrasplenic transplantation, mimicking central nervous system and primary vitreoretinal lymphoma pathology, respectively. Transcriptomic analysis revealed distinct signatures for lymphoma cells in the brain in comparison to the spleen as well as a small overlap of commonly regulated genes in both primary and secondary central nervous system lymphoma. Conclusion This in vivo tumour model preserves key features of primary and secondary central nervous system lymphoma and can be used to explore critical pathways for the central nervous system and retinal tropism with the goal to find new targets for novel therapeutic approaches

Abstract: Background Lipegfilgrastim has been shown to be non-inferior to pegfilgrastim for reduction of the duration of severe neutropenia (DSN) in breast cancer patients. This open-label, non-inferiority study assessed the efficacy and safety of lipegfilgrastim versus pegfilgrastim in elderly patients with aggressive B cell non-Hodgkin lymphoma (NHL) at high risk for chemotherapy-induced neutropenia. Patient and methods One hundred and one patients (median age, 75 years) were randomized to lipegfilgrastim or pegfilgrastim (6 mg/cycle) during six cycles of R-CHOP21. Results Lipegfilgrastim was non-inferior to pegfilgrastim for the primary efficacy endpoint, reduction of DSN in cycle 1. In the per-protocol population, mean (standard deviation) DSN was 0.8 (0.92) and 0.9 (1.11) days in the two groups, respectively; the adjusted mean difference between groups was − 0.3 days (95% confidence interval, − 0.70 to 0.19). Non-inferiority was also demonstrated in the intent-to-treat population. The incidence of severe neutropenia in cycle 1 was 51% (21/41) in the lipegfilgrastim group and 52% (23/44) in the pegfilgrastim group. Very severe neutropenia (ANC 0.1 × 109/L) in cycle 1 was reported by 5 (12%) patients in the lipegfilgrastim group and 8 (18%) patients in the pegfilgrastim group. However, over all cycles, febrile neutropenia (strict definition) was reported by only 1 (2%) patient in each treatment group (during cycle 1 in the lipegfilgrastim group and cycle 6 in the pegfilgrastim group). The mean time to absolute neutrophil count recovery (defined as ≥ 2.0 × 109/L) was 8.3 and 9.4 days in the two groups, respectively. Serious adverse events occurred in 46% of patients in each group; none were considered treatment-related. Eight patients died during the study (2 in the lipegfilgrastim group, 5 in the pegfilgrastim group, and 1 who died before starting study treatment). No deaths occurred during the treatment period, and all were considered to be related to the underlying disease.brbrConclusionsbrThis study shows lipegfilgrastim to be non-inferior to pegfilgrastim for the reduction of DSN in elderly patients with aggressive B cell NHL receiving myelosuppressive chemotherapy, with a comparable safety profile.brbrTrial registration number