Objective and methods: Neurofibromatoses are cancer-prone hamartomatoses that involve a variety of tissue and cell types. As part of a population-based clinical and genetic study of neurofibromatosis in northern Finland, all surgical and autopsy specimens of neurofibromatosis patients were retrieved and histologic slides were reviewed.
Results: Specimens were available for 69 of the 197 neurofibromatosis type 1 patients identified. Six malignant peripheral nerve sheath tumors and nine other malignant tumors were detected. In this study, the risk for neurofibromatosis-related malignancy was 8%. Nine neurofibromatosis type 1 patients died, at a mean age of 37 years. The cause of death was related to neurofibromatosis in eight.
Conclusions: The risk of developing malignant tumors and early death is increased in patients with neurofibromatosis, the most common malignancy being malignant peripheral nerve sheath tumors. These risks need to be recognized, and the families should be advised to seek genetic counseling and proper follow-up.