ABSTRACT
Primary central nervous system lymphoma (PCNSL) occurs primarily in older patients and has a worse prognosis than other extranodal lymphomas. Contemporary treatment is based on high-dose methotrexate (HD-MTX), which crosses the blood-brain barrier. Secondary CNS lymphoma (SCNSL) can occur concomitantly with systemic lymphoma or later at relapse and generally has a dismal outcome. We reviewed disease characteristics and outcomes of 103 patients (44 PCNSL and 59 SCNSL) treated at our center between 2015 and 2020. Median ages at diagnosis were 64 and 62 years, respectively. In both groups, diffuse large B cell lymphoma (DLBCL) was the major histologic type; in SCNSL, other types were also seen. SCNSL, in contrast with PCNSL, manifested with smaller tumors or cerebrospinal fluid positivity. For SCNSL the mean interval to brain involvement was 18 months (0-138). The overall survival had a trend to worse in SCNSL; median survival 11 months versus 61 months in PCNSL (p = 0.089). Progression-free survival was similar in both groups. A significant proportion of SCNSL patients with poor performance status could not obtain CNS-directed treatments. The strongest predictor of poor outcome was ECOG performance status 2 + at diagnosis for both groups. Charlson comorbidity index was predictive only for the PCNSL cohort. Tumor size was not prognostic for survival. The number of HD-MTX cycles correlated with survival, whereas the regimen itself and average cumulative dose of methotrexate did not play a role. Our study is in line with the recent literature and confirms ongoing challenges. We discuss how the outcomes of CNS lymphomas can be improved.
Subject(s)
Central Nervous System Neoplasms , Lymphoma, Large B-Cell, Diffuse , Humans , Aged , Methotrexate/therapeutic use , Neoplasm Recurrence, Local/drug therapy , Central Nervous System Neoplasms/drug therapy , Central Nervous System Neoplasms/epidemiology , Central Nervous System Neoplasms/pathology , Lymphoma, Large B-Cell, Diffuse/drug therapy , Lymphoma, Large B-Cell, Diffuse/pathology , Comorbidity , Retrospective Studies , Antineoplastic Combined Chemotherapy Protocols/therapeutic useABSTRACT
During autologous stem cell transplant, granulocyte colony-stimulating factors (G-CSF) serve the integral role of mobilizing hematopoietic cells into the peripheral blood for subsequent collection by leukapheresis. Filgrastim (Neupogen®) is a G-CSF and affects hematopoietic cells by stimulating growth and differentiation of neutrophils. Filgrastim-sndz (Zarxio®), a biosimilar of filgrastim, received landmark approval as the first biosimilar product approved by the FDA in the United States. As a result of the recent FDA approval, our medical center made the conversion in August 2016 from using filgrastim to filgrastim-sndz to provide patients the same benefits of the filgrastim injection at a reduced cost. This retrospective, observational cohort study evaluated the comparative efficacy of the filgrastim-sndz biosimilar in 147 patients who underwent mobilization prior to stem cell transplant with filgrastim between 1 August 2015 and 31 July 2016 or filgrastim-sndz between 1 September 2016 and 30 November 2017. The mean number of CD34 cells collected during apheresis was 7.38 × 106 in the filgrastim group and 8.86 × 106 in the filgrastim-sndz group. Filgrastim-sndz was significantly non-inferior, as the difference between filgrastim and filgrastim-sndz was -1.48 × 106 with an upper 95% confidence bound equal to -0.24 × 106 that did not include the non-inferiority margin of 1 × 106 (p = 0.0006). The median number of days of apheresis was 2 in both groups (p= 0.3273). In conclusion, the biosimilar product was non-inferior for mobilization and the conversion from filgrastim to filgrastim-sndz afforded patients similar efficacy for mobilization in stem cell transplant at a reduced cost.