Malignant peripheral nerve sheath tumors (MPNSTs) are uncommon but aggressive soft-tissue sarcomas in individuals with neurofibromatosis type 1 (NF1). Complete surgical excision remains essential for disease control 1. However, large NF1-associated tumors frequently display pronounced hypervascularity and fragile vasculature, which can lead to major intraoperative bleeding and limit safe resection 2 Preoperative embolization reduces operative blood loss in other surgical fields 3, 4 but dermatologic application remains limited because cutaneous tumors rarely possess identifiable, catheter-accessible feeding arteries. We report a case in which a targeted dual-modality embolization strategy enabled safe, near-bloodless resection of a giant hypervascular MPNST. A 68-year-old man with NF1 presented with acute bleeding from a paraspinal mass enlarging for over 10 years. Physical examination revealed a firm, dome-shaped, partially ulcerated 16 × 13 cm tumor on the upper back, with friable surface vessels and surrounding skin tension (Figure 1A). Contrast-enhanced magnetic resonance imaging (MRI) demonstrated marked arterial inflow from multiple intercostal arteries, with dense internal enhancement suggesting extensive hypervascularity (Figure 1B). Anticipating substantial blood loss, we planned preoperative arterial embolization to secure reliable vascular control. The procedure was performed in a standard catheterization room. Angiography showed that the primary feeders originated from the fifth through ninth intercostal arteries. To achieve sustained devascularization, we used a dual-modality technique: distal embolization with gelatin sponge particles followed by proximal coil placement (Figure 1C). Gelatin sponge was selected to occlude small peripheral branches within the tumor, while coils were used to interrupt proximal arterial flow and prevent collateral revascularization. Although risks include non-target embolization and surrounding skin ischemia, no such complications occurred. Following the procedure, patients typically require 24 hours of bed rest to prevent puncture-site hematomas, after which they can be discharged. However, our patient remained hospitalized pending surgery. Six days later, wide local excision was performed in a standard operating room. While surgery is typically performed within a few days post-embolization, the embolic effect of gelatin sponge particles persists for approximately 2 weeks, making our 6-day interval appropriate. Despite the tumor's size and vascularity, the procedure was completed with a total blood loss of only 50 mL. No transfusion was required, and intraoperative hemodynamics remained stable. A split-thickness skin graft was placed one week later without complication (Figure 1D). The patient was discharged 10 days postoperatively, following successful graft engraftment. Histopathology confirmed a low-grade MPNST arising within a plexiform neurofibroma, showing S-100 positivity and loss of H3K27me3 (Figure 2). No recurrence or metastasis was observed during a one-year follow-up. While preoperative embolization is routinely used for hypervascular tumors in other surgical specialties 3, 4, its limited adoption in dermatology may reflect differences in tumor biology: even when comparable in size, cutaneous tumors often lack enlarged, dominant feeding vessels amenable to catheterization. Nevertheless, selected tumors—particularly deep-seated, rapidly enlarging lesions—may demonstrate vascular anatomy suitable for embolization. Combined distal and proximal embolization strategies are commonly employed to balance immediate hemostasis with durable flow control 5 Our case illustrates that a simple combination of gelatin sponge and coils can achieve these goals without procedural complexity. Particulate embolization effectively reduces bleeding at the tumor–tissue interface, while coils provide sustained proximal control and limit early reperfusion. Three points merit emphasis. First, early vascular assessment of large soft-tissue tumors can reveal candidates for embolization. Second, collaboration with interventional radiology can meaningfully expand therapeutic options. Third, strategic embolization may transform the safety profile of high-risk tumor excision. This case demonstrates that a straightforward, dual-modality embolization technique provides effective vascular control for hypervascular MPNST, enabling safe and controlled surgery. The approach may be applicable to other hypervascular soft-tissue tumors when anatomical vascularity allows. The authors have nothing to report. The patient provided written informed consent for publication of their clinical details and associated images. The authors declare no conflicts of interest. The data that support the findings of this study are available from the corresponding author upon reasonable request.
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