Enhancing outcomes: neurosurgical resection in brain metastasis patients with poor Karnofsky performance score - a comprehensive survival analysis

Abstract

Background: A reduced Karnofsky performance score (KPS) often leads to the discontinuation of surgical and adjuvant therapy, owing to a lack of evidence of survival and quality of life benefits. This study aimed to examine the clinical and treatment outcomes of patients with KPS < 70 after neurosurgical resection and identify prognostic factors associated with better survival.

Methods: Patients with a preoperative KPS < 70 who underwent surgical resection for newly diagnosed brain metastases (BM) between 2007 and 2020 were retrospectively analyzed. The KPS, age, sex, tumor localization, cumulative tumor volume, number of lesions, extent of resection, prognostic assessment scores, adjuvant radiotherapy and systemic therapy, and presence of disease progression were analyzed. Univariate and multivariate logistic regression analyses were performed to determine the factors associated with better survival. Survival > 3 months was considered favorable and ≤ 3 months as poor.

Results: A total of 140 patients were identified. Median overall survival was 5.6 months (range 0-58). There was no difference in the preoperative KPS between the groups of > 3 and ≤ 3 months (50; range, 20-60 vs. 50; range, 10-60, p = 0.077). There was a significant improvement in KPS after surgery in patients with a preoperative KPS of 20% (20 vs 40 ± 20, p = 0.048). In the other groups, no significant changes in KPS were observed. Adjuvant radiotherapy was associated with better survival (44 [84.6%] vs. 32 [36.4%]; hazard ratio [HR], 0.0363; confidence interval [CI], 0.197-0.670, p = 0.00199). Adjuvant chemotherapy and immunotherapy resulted in prolonged survival (24 [46.2%] vs. 12 [13.6%]; HR 0.474, CI 0.263-0.854, p = 0.013]. Systemic disease progression was associated with poor survival (36 [50%] vs. 71 [80.7%]; HR 5.975, CI 2.610-13.677, p < 0.001].

Conclusion: Neurosurgical resection is an appropriate treatment modality for patients with low KPS. Surgery may improve functional status and facilitate further tumor-specific treatment. Combined treatment with adjuvant radiotherapy and systemic therapy was associated with improved survival in this cohort of patients. Systemic tumor progression has been identified as an independent factor for a poor prognosis. There is almost no information regarding surgical and adjuvant treatment in patients with low KPS. Our paper provides novel data on clinical outcome and survival analysis of patients with BM who underwent surgical treatment.

Keywords: Karnofsky performance status; brain metastases; neurosurgical resection; overall survival; systemic tumor progression.

Figure 1

Median overall survival of all patients with brain metastasis and Karnofsky Performance Score < 70 who underwent surgery.

Figure 2

Distribution of KPS before and after surgery. The difference in KPS before (black) and after (gray) surgery is shown as the mean with SD. The Wilcoxon signed-rank test was also performed. P-values are shown for each group. There was a significant difference in the postoperative KPS in the group with an initial KPS of 20% (p = 0.048). KPS, Karnofsky Performance Score.

Figure 3

Kaplan–Meier curves of overall survival (OS) in patients stratified by prognostic factors. Kaplan–Meier curves of OS in patients with Karnofsky Performance Score < 70 who underwent surgical resection stratified by (A) adjuvant radiotherapy, (B) adjuvant chemotherapy and immunotherapy, and (C) presence of systemic disease progression. The p-values of the log-rank tests are shown.