Differential Diagnosis Between Nasal Septal Schwannoma and Nasal Septal Neurofibroma.

Recently, as the authors experienced nasal septal schwannoma and nasal septal neurofibroma with similar clinical symptoms but different endoscopic findings, the authors tried to review all the literatures previously reported on the "Nasal septal schwannoma and Nasal septal neurofibroma." The aim of this study is to thoroughly review previously reported patients with nasal septal schwannomas and neurofibromas and to describe similar and different features focusing on the differential diagnosis between the 2 entities. On the basis of our review, the authors made some important conclusions. First, benign peripheral nerve tumors originating from the nasal septum are uncommon. Especially, nasal septal neurofibroma is extremely rare that only 5 patients were reported. So, more clinical reports of benign peripheral nerve tumors are necessary to elucidate the differences between nasal septal schwannoma and nasal septal neurofibroma. Second, there are some similar features between nasal septal schwannoma and nasal septal neurofibroma such as clinical symptoms, endoscopic findings, and treatment strategy. However, since there seem to be some differences in nasal endoscopic findings, they may be helpful for the provisional diagnosis, and so more patients should be reported to verify that point. Third, image study, especially magnetic resonance imaging (MRI), is considered to be a useful tool for differential diagnosis of benign peripheral nerve tumors originating from the nasal septum. So, more clinical reports reporting MRI findings are needed to verify the differences. Last, because of distinctive histologic appearances of benign peripheral nerve tumors, it is usually not difficult to make the distinction between nasal septal schwannoma and nasal septal neurofibroma. However, immunohistochemical stains including S-100 protein, calretinin, CD 34, factor XIIIa, and CD56 are necessary when it is difficult to differentiate between 2 disease entities.