Non-neurogenic sarcomas in four children and young adults with neurofibromatosis type 1

It is well known that children and young adults with neurofibromatosis type 1 (NF1) have a higher risk for non-neurogenic sarcomas than the general population, in addition to an increased risk for malignant peripheral nerve sheath tumor. When non-neurogenic sarcomas occur in early childhood, a subsequent malignant peripheral nerve sheath tumor can occur as a second malignant neoplasm, especially after alkylating agent chemotherapy and irradiation. This report includes the clinicopathologic features of non-neurogenic sarcomas and secondary malignant peripheral nerve sheath tumor in the context of four cases of NF1. The purpose is to emphasize that early diagnosis of NF1 and recognition of potential manifestations of non-neurogenic sarcomas are important for clinical care of these patients and their families.