Evans D G, Lye R, Neary W, Black G, Strachan T, Wallace A, Ramsden R T
Department of Medical Genetics, St Mary's Hospital, Manchester, UK.
J Neurol Neurosurg Psychiatry. 1999 Jun;66(6):764-7. doi: 10.1136/jnnp.66.6.764.
Some 4%-5% of those who develop vestibular schwannomas have neurofibromatosis type 2 (NF2). Although about 10% of these patients present initially with a unilateral vestibular schwannoma, the risk for a patient with a truly sporadic vestibular schwannoma developing contralateral disease is unknown.
A United Kingdom survey of 296 patients with NF2 was reviewed for laterality of vestibular schwannoma at presentation and the presence of other NF2 related features. The time to presentation of bilateral disease was calculated for patients presenting with a unilateral tumour. Mutation analysis of the NF2 gene was carried out on all available cases presenting initially with unilateral disease.
Of 240 patients with NF2 with vestibular schwannomas, 45 (18%; 32 sporadic, 13 familial) had either a unilateral tumour or delay in detection between the first and contralateral tumours. Among those tested for NF2 mutations, eight of 27 and nine of 13 were identified among sporadic and familial cases respectively. Sporadic cases showed a high female to male ratio and 19 of 32 have not as yet developed a contralateral tumour (mean 4.1 years after diagnosis of the first). Thirteen of 32 sporadic patients developed a contralateral tumour (mean 6.5 years after the first tumour diagnosis, range 0-22 years) compared with 11 of 13 familial patients (mean delay 5 years, range 0-16 years). Seven of the 45 patients had neither a family history of NF2 nor evidence of related tumours at initial presentation (six before the age of 35 years).
The risk of patients with sporadic unilateral vestibular schwannomata developing a contralateral tumour in the absence of family history or other features of NF2 is low, but those presenting with other neurogenic tumours in addition to vestibular schwannoma are at high risk of harbouring an NF2 mutation in at least a proportion of their somatic cells.
约4%-5%的前庭神经鞘瘤患者患有2型神经纤维瘤病（NF2）。尽管这些患者中约10%最初表现为单侧前庭神经鞘瘤，但真正散发型前庭神经鞘瘤患者发生对侧病变的风险尚不清楚。
回顾了一项英国对296例NF2患者的调查，以了解就诊时前庭神经鞘瘤的侧别及其他与NF2相关特征的存在情况。计算了单侧肿瘤患者出现双侧病变的时间。对所有最初表现为单侧病变的可用病例进行了NF2基因的突变分析。
在240例患有前庭神经鞘瘤的NF2患者中，45例（18%；32例散发，13例家族性）有单侧肿瘤或首次与对侧肿瘤之间检测延迟。在接受NF2突变检测的患者中，散发型病例中有27例中的8例、家族性病例中有13例中的9例被检测到突变。散发型病例中女性与男性比例较高，32例中有19例尚未发生对侧肿瘤（首次诊断后平均4.1年）。32例散发型患者中有13例发生了对侧肿瘤（首次肿瘤诊断后平均6.5年，范围0-22年），而13例家族性患者中有11例（平均延迟5年，范围0-16年）。45例患者中有7例在初次就诊时既无NF2家族史也无相关肿瘤证据（6例在35岁之前）。
在无家族史或NF2其他特征的情况下，散发型单侧前庭神经鞘瘤患者发生对侧肿瘤的风险较低，但除前庭神经鞘瘤外还伴有其他神经源性肿瘤的患者，其至少部分体细胞中携带NF2突变的风险较高。
