Impact of Extent of Resection on Overall Survival in World Health Organization Grade 4 Primary Spinal Cord Astrocytomas

BACKGROUND AND OBJECTIVE: Whether extent of resection (EOR) improves overall survival (OS) in World Health Organization (WHO) grade 4 primary spinal cord astrocytoma (SCA) remains controversial owing to limited and conflicting evidence. This study aimed to evaluate the impact of EOR on the prognosis of patients with WHO grade 4 primary SCA. METHODS: We retrospectively analyzed 59 cases of WHO grade 4 primary SCA (2014-2024) to assess the impact of EOR on survival with subgroup analysis based on tumor location and Ki-67 expression. RESULTS: In the whole cohort, Kaplan-Meier analysis showed no significant OS difference between the EOR ≥50% and EOR <50% groups (17 vs 10 months, P = .171). However, subgroup analyses found that EOR ≥50% significantly improved OS in noncervical SCA (36 vs 10 months, P = .034) and high Ki-67 SCA (16 vs 6 months, P = .016). CONCLUSION: This study demonstrates that the surgical benefit in WHO grade 4 primary SCA may be influenced by tumor location and Ki-67. We propose a hypothesis-generating conceptual framework to guide future research directions.