RT Journal Article
SR Electronic
T1 Schwannomatosis: a genetic and epidemiological study
JF Journal of Neurology, Neurosurgery & Psychiatry
JO J Neurol Neurosurg Psychiatry
FD BMJ Publishing Group Ltd
SP 1215
OP 1219
DO 10.1136/jnnp-2018-318538
VO 89
IS 11
A1 D Gareth Evans
A1 Naomi L Bowers
A1 Simon Tobi
A1 Claire Hartley
A1 Andrew J Wallace
A1 Andrew T King
A1 Simon K W Lloyd
A1 Scott A Rutherford
A1 Charlotte Hammerbeck-Ward
A1 Omar N Pathmanaban
A1 Simon R Freeman
A1 John Ealing
A1 Mark Kellett
A1 Roger Laitt
A1 Owen Thomas
A1 Dorothy Halliday
A1 Rosalie Ferner
A1 Amy Taylor
A1 Chris Duff
A1 Elaine F Harkness
A1 Miriam J Smith
YR 2018
UL http://jnnp.bmj.com/content/89/11/1215.abstract
AB Objectives Schwannomatosis is a dominantly inherited condition predisposing to schwannomas of mainly spinal and peripheral nerves with some diagnostic overlap with neurofibromatosis-2 (NF2), but the underlying epidemiology is poorly understood. We present the birth incidence and prevalence allowing for overlap with NF2.Methods Schwannomatosis and NF2 cases were ascertained from the Manchester region of England (population=4.8 million) and from across the UK. Point prevalence and birth incidence were calculated from regional birth statistics. Genetic analysis was also performed on NF2, LZTR1 and SMARCB1 on blood and tumour DNA samples when available.Results Regional prevalence for schwannomatosis and NF2 were 1 in 126 315 and 50 500, respectively, with calculated birth incidences of 1 in 68 956 and 1 in 27 956. Mosaic NF2 causes a substantial overlap with schwannomatosis resulting in the misdiagnosis of at least 9% of schwannomatosis cases. LZTR1-associated schwannomatosis also causes a small number of cases that are misdiagnosed with NF2 (1%–2%), due to the occurrence of a unilateral vestibular schwannoma. Patients with schwannomatosis had lower numbers of non-vestibular cranial schwannomas, but more peripheral and spinal nerve schwannomas with pain as a predominant presenting symptom. Life expectancy was significantly better in schwannomatosis (mean age at death 76.9) compared with NF2 (mean age at death 66.2; p=0.004).Conclusions Within the highly ascertained North-West England population, schwannomatosis has less than half the birth incidence and prevalence of NF2.