Abstract
Aims To identify the frequency of reports of sporadic schwannomatosis, the types of patients
affected, and the nerves affected.
Patients and Methods We identified all case reports and case series that reported on patients with sporadic
schwannomatosis according to established criteria.
Results The initial search yielded 1,597 studies, of which 15 were included. A total of 38
of 55 individuals met the inclusion criteria. The mean age of the patients was 48
years; 41% were male. Thirty-three patients had peripheral nerve tumors, and 17 had
spinal tumors. Twelve had tumors in both locations. Tumor distribution was unilateral
in 25 of 30 cases (83.3%) and segmental (limited to one limb or five or fewer contiguous
segments of the spine) in 28 of 38 cases (73.7%).
Conclusion This systematic review quantified the number of individuals who meet the criteria
for sporadic schwannomatosis and better described this population to facilitate the
classification of neurofibromatosis in regard to the 2005 consensus statement. Unilateral
or segmental distribution of nerve tumors are key aspects when dealing with multiple
noncutaneous schwannomas without involvement of the vestibular nerve.
Keywords
Schwannomas - peripheral nerve tumors - schwannomatosis - neurofibromatosis
