Neurofibromatosis type 1 (NF1) is characterized by the occurrence of multisystem tumors. The objective of this study was to analyze the demographic and oncological profile of 830 NF1-individuals regarding prevalence, type, and spectrum of malignancy.
Patients and methods
The medical records of patients diagnosed with NF1 with a median age of 22.1 years (range: 0.8–81.6 years) who were followed up for malignancies from 1999 to 2018 were retrospectively reviewed.
The prevalence of malignancy occurring in patients diagnosed with NF1 was 34.8% (289/830). The most common types of neoplasia encompassed tumors strictly associated with NF1, including plexiform neurofibromas (PNF; 200/830; 24.1%) and optic pathway gliomas (91/830; 11%). The prevalence of PNFs-transforming to malignant peripheral nerve sheath tumors (MPNST) was 3.5% (7/200). The prevalence of other tumors was 4.8% (40/830). One patient was diagnosed with acute myeloid leukemia (AML), thus the risk of hematological malignancies among all patients with NF1 was 0.1% (1/830). In the population of patients with malignancies, 43/289 (14.9%) individuals were diagnosed with more than one malignancy.
The odds ratio (OR) of malignancy in a studied cohort of patients with NF1 was 23 (p < 0.001), while the OR of hematological malignancy was 5.1 (p = 0.1) in comparison with the general population.