Objective: This study aimed to analyze the demographic characteristics and prognostic factors of malignant peripheral nerve sheath tumor (MPNST) in a Taiwanese population. Single-center treatment outcomes was also presented.

Material and Methods: This retrospective cohort study analyzed the medical records of 54 patients with pathological diagnoses of MPNSTs from 2005 to 2021 at a single institution. The primary endpoint was the 5-year overall survival rate of MPNST, and the secondary endpoint was recurrence-free 5-year survival. Variables including patient characteristics, metastasis status at initial diagnosis and surgical outcomes were analyzed with competing risk analysis.

Results: Among all 41 eligible patients diagnosed with MPNST, female predominance was noted, and the median age at diagnosis was 44 years. The most common site of lesion was found at the trunk (46.34%), and eight patients were diagnosed with notable metastasis. Twelve patients were diagnosed with type 1 neurofibromatosis (NF1). The 5-year overall survival rate was 36.84% and the 5-year recurrence-free survival was 28.95%. Metastasis diagnosed at presentation, large lesion sizes and recurrence were identified as significant poor prognostic factors of survival. Metastasis diagnosed at presentation was identified as the only significant risk factor of recurrence.

Conclusions: In our series, metastasis diagnosed at presentation, large lesion sizes and recurrence were identified as significant poor prognostic factors of survival. Metastasis was also identified as the only significant risk factor of recurrence. NF1-associated MPNSTs presented with significantly larger tumor sizes and additional treatment postoperatively did not significantly improve survival. The limitations of this study include its retrospective nature and sample size, and further large-scale study is needed.