Abstract: Objective To investigate the relevant prognostic factors of malignant peripheral nerve sheath tumors (MPNST). MethodsThe data of 33 patients with MPNST from September 2010 to December 2019 were reviewed. The 33 patients included 15 males and 18 females, and the median age was 42 years (ranged from 3 to 69 years). Eleven cases were neurofibromatosis type 1(NF-1)-associated MPNST, and 22 were sporadic MPNST. The distribution of lesion location included 20 cases of extremities and 13 cases of trunk. There were 28 cases with negative surgical margin and 5 cases with positive surgical margin. All patients underwent surgery. Five patients were treated with adjuvant radiotherapy and 9 patients with adjuvant chemotherapy. One patient with ROS1 mutation received crizotinib. Progression-free survival (PFS) and overall survival (OS) were analyzed as clinical outcomes. Prognostic factors were analyzed by Cox multivariate analysis. Results The follow-up time was 6-96 months. Eight patients had local recurrence (4 of extremities, 4 of trunk),and 14 patients were companied by  metastasis (6 of extremities, 8 of trunk). The 5-year progression'free survival rate was 38.3% and 5-year overall survival rate was 53.3%. Univariate analysis showed that the tumor size, the expression of S-100 and H3K27me3, and margin status were related with PFS (P<0.05), while the expression of S-100 and H3K27me3, margin status and radiotherapy were related with OS (P<0.05). Multivariate Cox regression analysis showed that S-100 and margin status were the independent factors affecting PFS (P<0.05), while margin status was the independent prognostic factor affecting OS (P<0.05). Conclusion S-100 and surgical margin are important factors affecting the prognosis of patients with MPNST. Individualized treatment should be made according to the clinicopathological features and gene detection results of patients.

Key words: font-size:10.5pt, Malignant peripheral nerve sheath tumors')">">Malignant peripheral nerve sheath tumors, Surgery, Prognosis