# Functional Outcomes After Reoperation for Recurrent Glioma: A Systematic Review and Meta-Analysis of Karnofsky Performance Status with Descriptive Health-Related Quality-of-Life Reporting

## TL;DR

This study reviews how repeat surgery for recurring brain tumors affects patients' functional abilities and quality of life.

## Contribution

The study provides a meta-analysis of functional outcomes after reoperation for recurrent gliomas using the Karnofsky Performance Status scale.

## Key findings

- A modest decline in Karnofsky Performance Status was observed post-surgery, though heterogeneity was high.
- Reoperation was not consistently linked to a decline in functional status across different studies.
- Health-related quality-of-life reporting remains inconsistent and limited in the literature.

## Abstract

Gliomas are the most common primary brain tumors in adults and frequently reoccur after initial surgical resection. With recurrence, repeat surgery is often considered; however, the impact of reoperation on patients’ overall well-being and functional status remains uncertain. In this study, we conducted a systematic review of the literature to evaluate the effect of reoperation for recurrent glioma on patients’ functional status. We found that patients’ functional outcomes were generally stable after repeat surgery, though individual variability was noted. Our findings suggest that reoperation can be performed without a substantial decline in functional status, supporting its consideration as part of multidisciplinary treatment planning. Our analysis highlights the need for more consistent measurement of patient outcomes to better guide future research in glioma management.

Background/Objective: Gliomas are the most common primary brain tumors in adults, with recurrence rates varying by tumor grade and initial treatment. Reoperation is a key strategy for managing recurrence; however, its impact on functional status and health-related quality of life (HRQoL) remains insufficiently defined. While HRQoL and neurocognitive outcomes have been described after primary treatment, far less is known following reoperation. This systematic review synthesizes available evidence on postoperative functional outcomes and summarizes HRQoL reporting in the reoperation literature. Methods: A systematic search of PubMed and Google Scholar retrieved 1336 articles. After removing duplicates (n = 76) and screening full texts (n = 42), 15 studies (total n = 1934; reoperation group n = 947) met the inclusion criteria. Studies were eligible if they employed validated functional or HRQoL instruments (e.g., Karnofsky Performance Status [KPS], FACT-G, SF-36, and EQ-5D-L). Due to limited and heterogeneous HRQoL reporting, only KPS could be aggregated for meta-analysis, and HRQoL measures were descriptively summarized. Results: Fixed-effect meta-analysis demonstrated a modest decline in postoperative KPS compared with preoperative scores (−3.28, 95% CI: −3.69 to −2.86; p < 0.001), though heterogeneity was high (I2 ≈ 97%). The random-effects model, accounting for interstudy variability, showed no significant overall change (+0.16 KPS, 95% CI: −4.04 to +4.35; p = 0.94; I2 ≈ 48%). The 95% prediction interval (−14.1 to +14.4) indicated that individual centers may observe either improvement or decline. Sensitivity analyses identified a small outlier study as a major contributor to heterogeneity; its exclusion did not materially alter the results. Conclusions: Across heterogeneous observational cohorts, reoperation for recurrent glioma was not associated with a consistent decline in functional status as measured by KPS, although substantial variability and uncertainty in outcomes remain. HRQoL reporting remains sparse and inconsistent, underscoring the need for prospective, multicenter studies employing standardized HRQoL instruments to better define quality-of-life trajectories after reoperation.