Malignant peripheral nerve sheath tumor; A report of three cases

We report three cases of malignant peripheral nerve sheath tumor (MPNST). One case was associated with neurofibromatosis type 1 (NF-1), while the other two were sporadic. All three patients who had undergone previous surgery at another unit developed local recurrence and underwent wide resection and reconstruction. The defects after tumor ablation were covered with a skin graft, superficial cervical artery perforator flap and latissimus dorsi myocutaneous flap, respectively. One case with NF-1 underwent adjuvant radiation therapy. All cases had no evidence of local recurrence after wide resection, while one with NF-I had lung metastases eight months after the surgery. Poor prognostic indicators for MPNST are as follows: 1) tumor size larger than 5 cm, 2) presence of NF-1, 3) insufficient resection due to small safety margin. Neither chemotherapy nor radiation therapy was reported to affect the survival rate. Therefore, it is essential to perform wide resection at the initial operation to improve the survival rate when a tumor grows and is suspected of being MPNST, especially in the case of NF-1 patients.