Abstract
BACKGROUND: Malignant peripheral nerve sheath tumors (MPNSTs) are rare soft tissue sarcomas with a high risk of recurrence and a poor prognosis, and there is a lack of knowledge regarding long-term follow-up and response to oncological treatment. AIMS: The aim of this study was to investigate what treatment the patients received and to examine the outcome for patients with MPNST. METHODS AND RESULTS: This is a retrospective study of patients treated for MPNST at Karolinska University Hospital between 2003 and 2022. Data regarding surgical and oncological treatment and follow-up were collected. Eighty-three patients were identified and included in the study. Tumor grade is available for 72 patients, of which 64 had high-grade tumors. Seventy-nine patients were primarily operated on. Twelve patients presented with distant metastases at diagnosis. Another 37 patients developed local recurrence or distant metastases during follow-up; the median time from surgery to recurrence was 10.5 months (1-95 months, n = 36). The overall mortality rate during the study period was 44% (n = 82). Twenty-seven patients received palliative systemic treatment. The most used therapy for first-line palliative systemic treatment was doxorubicin and ifosfamide. The disease control rate for first-line treatment was 33% (n = 21). The mean overall survival for the cohort was 132 months (95% CI 107-157 months). CONCLUSION: Forty-five percent of the patients in this material were diagnosed with recurrent disease and most patients treated with palliative systemic therapy experienced brief disease control following treatment. Among patients with MPNST treated with first-line palliative oncological treatment, doxorubicin and ifosfamide have the highest disease control rates. The study also identified a few patients with long-term treatment responses, with four patients alive more than 2 years after starting palliative oncological treatment.