Schwannomas are neoplasms composed of Schwann cells, which are responsible for maintaining the myelin sheath of peripheral neurons. A loss of function in the NF2 gene, which codes for the protein merlin, often gives rise to these tumors.1 Abnormalities in this gene are also a causative factor in neurofibromatosis, a disorder leading to single or multiple nerve cell tumors. An estimated 3% of schwannoma cases will be associated with neurofibromatosis; thus, a family history of neurofibromatosis is an important clinical factor in these conditions.2 Cranial nerve schwannomas are a relatively common finding and are discovered in 3% to 4% of patients at autopsy. Peripheral schwannomas, although not uncommon, have a lower incidence of 0.6 per 100,000 people annually, with the vast majority of these tumors found on the flexor surfaces of limbs.1 Primary tumors of the penis, however, are exceedingly rare, with penile schwannomas even rarer, still. An estimate of as few as 1640 cases of penile cancer were diagnosed in the United States in 2014.3

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