A 53 year old female presented to the ER complaining of one month of progressive lower back pain with radiation to her right leg, and associated severe bilateral tight hamstrings. The patient was unable to walk, stand or sleep due to the pain. Family history was positive for her father and sister having questionable spinal cord tumors. Physical examination revealed a positive straight leg test on the right. MRI revealed a large lesion at T11 (1×2 inches), L1 (1×0.5 inches), some small lesions at L3, and others small lesions segments in the lumbar region. After surgical excision, histology of the tumor revealed Schwannomas (Image).
Patients with multiple schwannomas and absence of typical signs of NF1 and NF2 have been postulated to compose a distinct subclass of neurofibromatosis termed Schwannomatosis. This is a form of genetic disorder that has been recently recognized. Schwannomatosis was first reported in 1973 as neurofibromatosis type 3 (NF3). In 2007, a candidate gene for schwannomatosis, called SMARCB1tumor suppressor gene, was identified. However, the NF2 gene and possibly other genes may also be involved in causing schwannomatosis. Unlike NF1 and NF2, Schwannomatosis does not have a clear pattern of inheritance. MRI is the gold standard for detection. The diagnostic criteria includes: 2 or more pathologically ascertained schwannomas without symptoms of 8th nerve dysfunction at age >30-years or 2 or more pathologically sampled schwannomas in an anatomically limited distribution without symptoms of 8th nerve dysfunction at any age. Our case can be considered as a possible schwannomatosis, since the patient’s age >30-years old, she had more than 2 schwannomas in the spinal cord with histological confirmations and no symptoms of 8thcranial nerve dysfunction.
We report a case of Schwannomatosis (neurofibromatosis type 3) with multiple Schwannomas of the thoracic and lumbar spinal cord. Similar reports may provide the authors with a better understanding of the clinical scenario and help elucidate the best treatment options.