Objects: Patients with neurofibromatosis type 1 (NF1) are predisposed to developing soft tissue sarcomas (STS).
Materials and methods: We report on four cases of STS diagnosed in locally advanced, unresectable stages in children with NF1 (three girls, one boy; age = 8 months-14 years). All patients received protocols for STS: Cooperative Weichteilsarkomstudie 91, 96 and 2002. One patient with limb rhabdomyosarcoma entered complete remission but developed late metastatic relapse and died of progression despite complete excision and autologous bone marrow transplantation. The other patient with bladder rhabdomyosarcoma died of neutropenia-related sepsis without remission. Patients with malignant peripheral nerve sheet tumour and malignant triton tumour located in the pelvis did not respond to therapy. One of them died of disease progression, while the other is disease-free 6 years post-therapy after mutilating tumour resection.
Conclusion: STS in NF1 seem to display poor prognosis in spite of combined therapy; thus, children with NF1 should remain under detailed control of the oncologist.