Neurofibromatosis type 1 (NF1) is a common autosomal dominant condition affecting approx 1 in 3500 persons (1 ). Individuals with NF1 have a small but significant risk of developing cancers, primarily derived from neural crest tissues, such as astrocytic brain tumors and malignant peripheral nerve sheath tumours (1 ). In addition, children with NF1 are at increased risk of developing malignant myeloid disorders, particularly a form of myelodysplasia termed juvenile myelomonocytic leukemia (JMML) (2 –4 ). Thus, NF1 may be considered an heritable cancer syndrome, a group of disorders characterized by an increased risk of developing primary cancers.
