Metastatic Malignant Peripheral Nerve Sheath Tumor With NF1 Successfully Treated With 'Gradual Subtraction' ICE Chemotherapy

Background: Prognosis of metastatic malignant peripheral nerve sheath tumor (MPNST) is poor and the role of chemotherapy is controversial. There has been no report of metastatic MPNST with a good prognosis without surgery for metastases. Case Report: A 40-year-old man with neurofibromatosis type 1 (NF1)-related MPNST on his shoulder with multiple lung metastases visited our hospital. After two cycles of chemotherapy with ifosfamide, carboplatin and etoposide (ICE), the primary lesion and lung metastases had shrunk. The primary lesion was resected with negative margins. Subsequently, 'gradual subtraction' ICE was administered, wherein the dose was reduced and the treatment interval was increased. After 14 courses of ICE over a period of 2 years, the lung metastases disappeared; there has been no recurrence for over 12 years. Conclusion: ICE can be an excellent, inexpensive treatment for NF1-related MPNST. 'Gradual subtraction' chemotherapy allowed us to maintain long-term efficacy, induce tumor dormancy, and reduce side-effects.