Abstract
Objectives To determine the specificity of the current clinical diagnostic criteria for neurofibromatosis type 2 (NF2) relative to the requirement for unilateral vestibular schwannoma (VS) and at least two other NF2 related tumours.
Methods We interrogated our Manchester NF2 database, which contained 205 individuals meeting NF2 criteria who initially presented with a unilateral VS. Of these 83 (40.7%) went on to develop a contralateral VS. We concentrated our genetic analysis on a group of 70 who initially fulfilled NF2 criteria with a unilateral vestibular schwannoma and at least two additional non-intradermal schwannomas.
Results Overall 5/70 (7%) individuals with unilateral VS and at least two other schwannomas had a pathogenic or likely pathogenic LZTR1 mutation. Twenty of the 70 subsequently developed bilateral disease. Of the remaining 50, 5 (10%) had a germline LZTR1 mutation, equivalent to the number (n=5) with a germline NF2 mutation.
Conclusion The most common etiology for unilateral VS and two additional NF2-associated tumors in this cohort was mosaic NF2. Germline LZTR1 and germline NF2 mutations were equally common in our cohort. This indicates that LZTR1 must be considered when making a diagnosis of NF2 in the presence of unilateral VS in individuals without a germline NF2 mutation
Methods We interrogated our Manchester NF2 database, which contained 205 individuals meeting NF2 criteria who initially presented with a unilateral VS. Of these 83 (40.7%) went on to develop a contralateral VS. We concentrated our genetic analysis on a group of 70 who initially fulfilled NF2 criteria with a unilateral vestibular schwannoma and at least two additional non-intradermal schwannomas.
Results Overall 5/70 (7%) individuals with unilateral VS and at least two other schwannomas had a pathogenic or likely pathogenic LZTR1 mutation. Twenty of the 70 subsequently developed bilateral disease. Of the remaining 50, 5 (10%) had a germline LZTR1 mutation, equivalent to the number (n=5) with a germline NF2 mutation.
Conclusion The most common etiology for unilateral VS and two additional NF2-associated tumors in this cohort was mosaic NF2. Germline LZTR1 and germline NF2 mutations were equally common in our cohort. This indicates that LZTR1 must be considered when making a diagnosis of NF2 in the presence of unilateral VS in individuals without a germline NF2 mutation
| Original language | English |
|---|---|
| Pages (from-to) | 87 |
| Number of pages | 92 |
| Journal | Neurology |
| Volume | 88 |
| Issue number | 1 |
| Early online date | 16 Nov 2016 |
| DOIs | |
| Publication status | Published - 3 Jan 2017 |