Spinal and Paraspinal Malignant Peripheral Nerve Sheath Tumors (MPNSTs): Survival, Local Recurrence, and the Relative Importance of Resection Extent and Margin Status
Leevi Toivonen, Anton DenisovStudy Design
Systematic literature review.
Objectives
To characterize clinical features, treatment patterns, and outcomes of spinal and paraspinal malignant peripheral nerve sheath tumors (MPNSTs) and to evaluate the relative prognostic importance of extent of resection and surgical margin status.
Methods
A search of published cases of spinal and paraspinal MPNSTs with individual-level treatment and outcome data was performed. Overall survival (OS) and local recurrence-free survival (LRFS) were analyzed using Kaplan–Meier estimates and multivariable Cox regression. Competing-risk regression was used to assess local recurrence while accounting for death as a competing event. Model performance was compared using the Akaike information criterion.
Results
Among 230 included patients, median OS was approximately 15 months, and median RFS was approximately 25 months, with a high early local recurrence rate. Metastatic disease at presentation was the strongest predictor of death (HR 3.02, 95% CI 1.57–5.84). Gross total resection was independently associated with improved OS (HR 0.37, 95% CI 0.23–0.58) and LRFS (HR 0.38, 95% CI 0.20–0.72) and demonstrated superior model performance over surgical margin status. In a competing-risk analysis, intralesional resection was independently associated with increased local recurrence (sub-distribution HR 1.78, 95% CI 1.09–2.92), while neurofibromatosis type 1 also conferred elevated local recurrence risk.
Conclusions
Spinal and paraspinal MPNSTs are characterized by poor survival and high early local recurrence. Extent of resection is the dominant surgical determinant of OS, whereas margin status primarily influences LRFS. These findings support the hypothesis that macroscopic total resection should be pursued even when negative margins cannot be achieved.