Enrico Martin

90 Chapter 5 Introduction Malignant peripheral nerve sheath tumors (MPNSTs) are aggressive soft tissue sarcomas (STS) that can occur at any anatomical site. 1 Approximately 25-50% of all patients are known to have neurofibromatosis type 1 (NF1). 2–6 The diagnosis of an MPNST can be difficult as patients may present with similar symptoms compared to their benign counterparts and MRI studies cannot distinguish a malignancy with high precision. 7–9 This can especially be troublesome in patients with NF1 that develop multiple benign nerve sheath tumors. Surgical resection is the only curative treatment option in localized MPNSTs. 4,10 Radiotherapy has an important role in decreasing local recurrence rates, but does not affect survival. 4,11,12 The exact role for chemotherapy is also subject of controversy, but is advocated by some as adjuvant treatment in large and deep MPNSTs. 13,14 Unfortunately, despite curative aims of aggressive treatment including clear surgical margins, MPNSTs regularly recur and metastasize in up to 60% of patients. 2–4,15,16 MPNSTs are rare tumors and exact treatment strategies may differ between surgeons, because patients can present at different surgical subspecialties due to their origin in nervous tissue and occurrence in NF1. While surgical oncologist consider MPNSTs as part of their sarcoma population requiring radical excision, 17,18 plastic surgeons and neurosurgeons operating peripheral nerve lesions regard them as a malignant form of nerve sheath tumor, which are treated by nerve-sparing surgery. 19,20 Such a difference in perspective could affect clinical decision-making. This study investigated treatment recommendations and differences in opinions between surgical subspecialties treating MPNSTs on preoperative diagnostics, surgical decision-making, and the use of multimodal therapy in localized MPNSTs. Methods Study design and survey instrument A survey was constructed by two authors (E.M. and J.H.C.) and tested internally with all co-authors from different surgical subspecialties. A secure electronic data capturing tool (REDCap) provided by the Dutch Plastic Surgery Society (NVPC) was used to construct the survey. This study is part of a larger survey addressing both oncological and reconstructive treatment considerations for localized MPNST. A total of 18 questions (30 in total) were used for this study, of which seven were for demographical purposes. The complete survey can be found in Supplementary File 1 . Approval for this study was obtained from our institutional review board.