Most MPNSTs are generally considered high-grade sarcomas [1
]. Approximately 40% of patients developed local recurrence, and the overall five-year survival rate was 34–43% [6
]. On the other hand, epithelioid variants are rare and are estimated to comprise 5% or fewer of MPNSTs [1
]. Thus, biologic behavior and prognosis are unclear. However, the largest series, which included 26 cases and was reported by Laskin et al. [3
], showed that although most patients were treated with wide excision, four developed distant metastases and three died of the disease within three years. High incidence of metastasis (seven of 14 cases) was also reported by Lodding et al. in 1986 [2
Aggressive surgery is considered the only procedure to improve prognosis of the MPNST [6
], and the response to chemotherapy against MPNST is poor according to previous reports [8
]; however, several reports have demonstrated that chemotherapy can be effective [9
]. Although the standard regimens are still investigative, ifosfamide and doxorubicin are considered key drugs for advanced soft tissue sarcomas [11
]. In our clinical case, administering ifosfamide and doxorubicin with mesna showed good efficacy on the multiple lung metastases, with low-grade toxicities including myelosuppression and hair loss.
Surgical management of lung metastases may be effective in select situations [13
]. Two reports on MPNST demonstrated poor survival rates after development of pulmonary metastases; however, prolonged survived cases with thoracotomy were also described [7
]. As for nonosteogenic sarcoma, Creagan showed the overall 5-year survival following the first thoracotomy was 29% with a median survival of 18 months [14
]. The present case involved the development of disseminating lung nodules ten weeks postoperatively; however, chemotherapy provided a favorable response to all metastatic lesions. Subsequently, thoracoscopic resection of the remaining three lesions was performed to both eliminate the sarcoma and allow histological evaluation of the response to chemotherapy. Based on the histological findings that two of the three lesions showed remaining sarcoma, continuing the same regimen without surgery may risk inducing development of chemotherapy-resistant sarcoma cells.