# Associations Between Early Neurosurgical Workflow and Survival in Primary Central Nervous System Lymphoma: A Single-Center Retrospective Study

## TL;DR

This study suggests that early neurosurgical decisions, like corticosteroid use and biopsy timing, may affect survival in patients with a rare brain tumor called PCNSL.

## Contribution

The study identifies early neurosurgical workflow factors as potentially modifiable influences on PCNSL survival outcomes.

## Key findings

- Pre-biopsy corticosteroid exposure is linked to less favorable survival in PCNSL patients.
- Delays between MRI and biopsy are associated with worse survival outcomes.
- Biopsy-to-induction timing does not significantly affect early survival outcomes.

## Abstract

Primary central nervous system lymphoma (PCNSL) is a rare but aggressive brain tumor for which critical clinical decisions are often made before patients enter formal oncologic care. In routine practice, neurosurgeons frequently control the early diagnostic phase through corticosteroid administration and biopsy timing. In this study, we explore whether these early neurosurgical workflow decisions are associated with patient survival, observing that pre-biopsy corticosteroid exposure and delays between MRI and biopsy are associated with less favorable survival trajectories, with a clear separation of survival patterns despite the absence of conventional statistical significance. Although limited by sample size, these findings suggest that the earliest phase of care may represent a modifiable window with potential prognostic relevance. Increased interdisciplinary awareness of this early diagnostic period may contribute to improved PCNSL management strategies.

Primary central nervous system lymphoma (PCNSL) is an aggressive malignancy for which early management decisions frequently occur within neurosurgical workflows prior to oncologic treatment. In this retrospective single-center study, we aimed to explore whether early neurosurgical workflow characteristics are associated with survival outcomes in patients with PCNSL. Consecutive adult patients diagnosed with PCNSL between 2012 and 2022 were included, and the variables of interest comprised pre-biopsy corticosteroid exposure, the interval between diagnostic magnetic resonance imaging (MRI) and stereotactic biopsy, and the time from biopsy to initiation of high-dose methotrexate–based induction therapy. All patients were treated under a standardized hematology protocol to limit systemic treatment heterogeneity. Overall survival (OS) and progression-free survival (PFS) were calculated from the date of diagnostic biopsy, and survival analyses were performed using Kaplan–Meier methods and log-rank testing. Twenty-nine patients met the inclusion criteria. Median OS and PFS were not reached in steroid-naïve patients, whereas pre-biopsy corticosteroid exposure was associated with consistently shorter survival trajectories, with a clear separation of the survival curves, despite conventional statistical significance not being reached. Similarly, median OS and PFS were not reached in patients undergoing biopsy within 7 days of MRI, and an MRI-to-biopsy interval exceeding 7 days demonstrated an unfavorable survival trajectory compared with earlier biopsy; biopsy-to-induction timing did not show a measurable association with early survival outcomes. Established prognostic stratification using Memorial Sloan–Kettering Cancer Center classes showed expected survival discrimination within the cohort, supporting internal validity. Given the limited sample size and retrospective design, all findings should be interpreted as exploratory associations rather than evidence of causality. These results suggest that early neurosurgical workflow characteristics, particularly empiric pre-biopsy corticosteroids avoidance and diagnostic delay minimization, may be associated with early survival trajectories in PCNSL and warrant further evaluation in larger prospective studies.