Sympathetic schwannoma: a case report.

Schwannomas (also known as Neurilemomas or Neurinomas) are benign tumors of the nervous system that originate in the neural sheath and most commonly occur as solitary encapsulated subcutaneous tumors in otherwise healthy individuals. When they present as multiple tumors, they are histologically indistinguishable from the solitary tumors and, in such a case, they may be associated with neurofibromatosis 2 (NF2) in which the sensory roots of the cranial and spinal nerves are affected more often than the motor roots and the hallmark tumor of which is a vestibular schwannoma (also known as acoustic neuroma). They also may exist as a distinct clinical entity without any stigmata of neurofibromatosis known as schwannomatosis. Generally, schwannomas are less than 5 cm in diameter but sizes greater than 14 cm have been reported. They present as slow growing masses and may present with pain or neurological symptoms. Here we report a patient with sympathetic schwannoma who presented with right flank pain.