Improved Glioblastoma Survival Across Sweden From 1999 to 2023: Nationwide Analysis Highlights Impact of Demographic and Prognostic Factors When Analysing Regional Variations—A Comprehensive Analysis of 7669 Glioblastoma Patients

Background and Purpose

Glioblastoma, the most prevalent primary malignant brain tumour, has a median survival of 9–11 months for unselected populations. This nationwide Swedish study (1999–2023) assessed survival, regional differences and their correlation to clinical prognostic factors in patients diagnosed with glioblastoma.

Patient/Material and Methods

Using the Swedish Registry for Primary Brain Tumours, 7669 patients with glioblastoma were identified. Data on overall survival (OS), relative survival (RS), age, sex, preoperative performance status (PPS), tumour size, surgical resection grade and oncological treatments were collected. Cox analyses were conducted stepwise, initially by regions, then adjusted for demographic and clinical variables.

Results

Median OS was 10.5 months, with a 2-year OS rate of 17% and a similar 2-year RS of 0.17. Median OS improved from 9.2 months (1999–2009) to 11.2 months (2018–2023, p < 0.001), whereas 1-year RS increased from 0.38 to 0.47. Gross total resection, concomitant chemoradiotherapy and MGMT methylation were associated with significantly longer survival. Partial resection was superior to biopsy. In univariate analysis of regional differences from 2018 to 2023, the most densely populated region had a better survival than the other regions; however, after logistic regression analysis, adjusting for demographic and clinical factors, differences were statistically minor and not clinically significant.

Conclusion

In this nationwide cohort of nearly all Swedish GBM patients over 25 years, OS improved significantly over time and was associated with extent of resection, concomitant chemoradiotherapy and MGMT methylation. After adjustment for demographic and clinical factors, there were no clinically relevant regional differences.