Mosaic Neurofibromatosis Type 1: A Systematic Review
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Published on: May 17, 2024
Maria Teresa García-Romero1,2, Patricia Parkin2, Irene Lara-Corrales1,2
1Dermatology Section, Hospital for Sick Children, University of Toronto, Toronto, Ontario, Canada.
Abstract:
Confusion is widespread regarding segmental or mosaic neurofibromatosis type 1 (MNF1). Physicians should use the same terms and be aware of its comorbidities and risks. The objective of the current study was to identify and synthesize data for cases of MNF1 published from 1977 to 2012 to better understand its significance and associations. After a literature search in PubMed, we reviewed all available relevant articles and abstracted and synthetized the relevant clinical data about manifestations, associated findings, family history and genetic testing. We identified 111 articles reporting 320 individuals. Most had pigmentary changes or neurofibromas only. Individuals with pigmentary changes alone were identified at a younger age. Seventy-six percent had localized MNF1 restricted to one segment; the remainder had generalized MNF1. Of 157 case reports, 29% had complications associated with NF1. In one large case series, 6.5% had offspring with complete NF1. The terms "segmental" and "type V" neurofibromatosis should be abandoned, and the correct term, mosaic NF1 (MNF1), should be used. All individuals with suspected MNF1 should have a complete physical examination, genetic testing of blood and skin, counseling, and health surveillance.
Insights
Mosaic neurofibromatosis type 1 (MNF1) is often confused. This review clarifies MNF1, recommending the term mosaic NF1 for all cases and emphasizing comprehensive evaluation for affected individuals.
Area of Science:
- Genetics
- Dermatology
- Medical Genetics
Background:
- Neurofibromatosis type 1 (NF1) is a genetic disorder.
- Segmental or mosaic NF1 (MNF1) causes confusion among physicians.
- Standardized terminology and understanding of MNF1 are lacking.
Purpose of the Study:
- To synthesize data on mosaic NF1 (MNF1) from published literature.
- To clarify the significance and associations of MNF1.
- To establish consistent terminology for MNF1.
Main Methods:
- Literature search of PubMed for MNF1 cases (1977-2012).
- Abstraction and synthesis of clinical data from 111 articles reporting 320 individuals.
- Review of manifestations, associated findings, family history, and genetic testing.
Main Results:
- Most individuals presented with pigmentary changes or neurofibromas.
- Localized MNF1 occurred in 76% of cases; generalized MNF1 in the remainder.
- 29% of case reports had NF1-associated complications; 6.5% had offspring with complete NF1.
Conclusions:
- The terms "segmental" and "type V" neurofibromatosis should be abandoned in favor of mosaic NF1 (MNF1).
- Individuals with suspected MNF1 require thorough physical examination and genetic testing.
- Comprehensive health surveillance and genetic counseling are essential for MNF1 patients.
