"The name neurofibromatosis type 2 has been described as a misnomer because neurofibromas are not a common part of its constellation of abnormalities, and it is not pathologically related to neurofibromatosis type 1 5. This inconsistency arose from the early 20th century misunderstanding that NF2 represented a 'central' variant of the more common 'peripheral' neurofibromatosis type 1 10."
"Neurofibromatosis type 2 (NF2), more accurately known as NF2-related schwannomatosis, is a rare autosomal dominant neurocutaneous disorder (phakomatosis) manifesting as the development of multiple CNS tumours."
"The condition has been more accurately described by alternative names such as multiple inherited schwannomas, meningiomas and ependymomas (MISME) and NF2-related schwannomatosis 4,11, the latter having been adopted as preferred nomenclature in the 2022 diagnostic criteria 11."
"an identical NF2 pathogenic variant in ≥2 anatomically distinct NF2-related tumours (schwannoma, meningioma, and/or ependymoma)"
"NF2 pathogenic variant in an unaffected tissue such as blood"
"The NF2 gene is located on the long arm of chromosome 22 (22q12) and encodes the merlin protein (also known as "schwannomin"). It plays a role in contact inhibition of growth and has a tumour-suppressor function, at least in part, through this mechanism 9. Although variably expressed throughout the body during human development, merlin is highly expressed in adult neuronal cells, Schwann cells, and meningeal cells. Mutations in NF2 cause loss of protein function, resulting in a predisposition to tumour formation throughout the nervous system 9."
"Importantly, neurofibromatosis type 2 is not associated with an increased risk of malignant tumours 12. However, many tumours have somatic mutations in NF2, which are distinct from the germline mutations that cause neurofibromatosis type 2 12."
"The name neurofibromatosis type 2 has been described as a misnomer because neurofibromas are not a common part of its constellation of abnormalities, and it is not pathologically related to neurofibromatosis type 1 5. This inconsistency arose from the early 20th century misunderstanding that NF2 represented a 'central' variant of the more common 'peripheral' neurofibromatosis type 1 10."
"The condition has been more accurately described by alternative names such as multiple inherited schwannomas, meningiomas and ependymomas (MISME) and NF2-related schwannomatosis 4,11, the latter having been adopted as preferred nomenclature in the 2022 diagnostic criteria 11."
"The condition has been more accurately described by alternative names such as multiple inherited schwannomas, meningiomas and ependymomas (MISME) and NF2-related schwannomatosis 4,11, the latter having been adopted as preferred nomenclature in the 2022 diagnostic criteria 11."
"either 2 major OR 1 major and 2 minor criteria (as below)"
Expected headings
"Major criteria"
"Minor criteria"
"Associations"
"The condition has been more accurately described by alternative names such as multiple inherited schwannomas, meningiomas and ependymomas (MISME) and NF2-related schwannomatosis 4,11, the latter having been adopted as preferred nomenclature in the 2022 diagnostic criteria 11."
"Confirmed bilateral vestibular schwannomas are diagnostic of neurofibromatosis type 2 7. However, care should be taken because bilateral internal acoustic meatus masses are not specific for vestibular schwannoma and can represent, for example, sarcoidosis or metastases 6; thus, bilateral internal acoustic meatus masses must be unequivocally characterised as schwannomas before this criterion is applied."
"Can count >1 of a type (e.g. 2 distinct schwannomas would count as 2 minor criteria):"
"Can count only once (e.g. bilateral cortical cataracts count as a single minor criterion):"
"Confirmed bilateral vestibular schwannomas are diagnostic of neurofibromatosis type 2 7. However, care should be taken because bilateral internal acoustic meatus masses are not specific for vestibular schwannoma and can represent, for example, sarcoidosis or metastases 6; thus, bilateral internal acoustic meatus masses must be unequivocally characterised as schwannomas before this criterion is applied."