Journal des biomarqueurs moléculaires et du diagnostic

A Study on Schwannomas: Morphology Alone is Insufficient

Abstract

Gayatri Gogoi, Jasmine Teronpi, Linda Lamngaiching Changsan, Projnan Saikia and Mondita Borgohain

Schwannomas constitute one of the most common benign peripheral nerve sheath tumors. Schwannomas can occur anywhere in the body occasionally with unusual presentation. FNB does not appear to provide an accurate preoperative diagnosis. Complete excision of the mass should be the goal of surgical excision. In this case series, we studied various clinicomorphological features of schwannomas for duration of one year. Immunostaining were done using anti-S100 protein and a panel of antibody to confirm the diagnosis cases as well as in cases whose histological picture simulated schwannoma. Out of the 9 cases in our study, two cases showed unusual presentations. Schwannoma often gives a differential diagnosis of similar benign soft tissue tumors. All cases were benign schwannoma except one case with rectal growth turned out to be gastrointestinal stromal tumor on immunohistochemistry. Herein, we are discussing about the various histological pictures of schwannoma, diagnostic difficulties encountered in histopathology and the indispensable role of immunohistochemistry in confirmation. Classic schwannoma picture in histology is insufficient to confirm the diagnosis. Cellular schwannoma often posed a differential diagnosis of other tumors in histology such as spindle cell tumor. Palisading of nuclei is not unique to schwannoma as seen in the case of gastrointestinal stromal tumor. It can also occur in leiomyoma, leiomyosarcoma, gastrointestinal stromal tumor, calcifying aponeurotic fibroma, and even in non-neoplastic smooth muscle lesion. Gastrointestinal stromal tumor may harbor a picture of classic schwannoma and should be careful in gastro intestinal site.