Prognostic Factors and Predictive Nomogram of Malignant Peripheral Nerve Sheath Tumor Patient Survival: A Population-Based Retrospective Surveillance, Epidemiology, and End Results Database Analysis

Introduction: Malignant peripheral nerve sheath tumors (MPNSTs) are exceedingly rare, highly aggressive sarcomas most commonly affecting peripheral nerves of the proximal upper and lower extremities. Given the rarity of these tumors, there is limited data available to aid in clinical decision-making and prognostication. Within this study, we sought to characterize MPNST patient survival determinants based on the nationwide Surveillance, Epidemiology, and End Results (SEER) database.

Methods: SEER 18 database was queried for MPNST between 2000 and 2020. Patient demographics, tumor histologic characteristics and treatment data was extracted and analyzed. A predictive nomogram was built to predict MPNST patient 5- and 10-year survival probability.

Results: A total of 2832 patients were identified and included in the analysis. The overall survival rate at 1-, 2-, 5-, and 10-years was 76%, 64%, 50%, and 41%, respectively. Multivariable analysis revealed that male sex (p < 0.05), age 18 years or older (p < 0.001), rhabdomyoblastic differentiation (p < 0.05), tumor size >3 cm (p < 0.001), tumor location in the spine (p < 0.01), non-surgical management (p < 0.001), gross total resection combination with adjuvant treatments except radiation (p < 0.05) were associated with worse overall survival. Female sex (p < 0.05), age < 18 years (p < 0.001), tumor location in the brain (p < 0.01) and surgical management (p < 0.001) were associated with better overall survival. Patients that received gross total resection (GTR) with radiation, subtotal resection (STR) or STR with radiation had no difference in OS when compared to patients receiving GTR alone. Patients that received any other treatment or no treatment at all had worse OS when compared to patients that received GTR alone (p < 0.001). The nomogram demonstrated good accuracy in predicting survival at 5- and 10-years with C-index of 0.67 (95% CI of 0.64 to 0.70) and AUC of 0.71.

Conclusion : Patient’s age, sex and race, tumor histology, location and size as well as the treatment modality used were significant predictors of overall survival. Surgical treatment in general offered a significant survival advantage over other treatment modalities. When used as a stand-alone modality, surgical treatment extent itself did not prove to be a significant survival determinant.