Rare Form of Schwannoma as a Purely Hemorrhagic Cystic Tumor Located in an Intermuscular Plane

A schwannoma is a benign peripheral nerve sheath tumor arising from Schwann cells. Most schwannomas are solid tumors and cystic degeneration and hemorrhage can be seen (1). A benign schwannoma can display degenerative changes, such as hyalinization, hemorrhaging, calcification, and cyst formation. These changes are usually partially visible in the tumors (1-6). Few reports have described a purely cystic schwannoma (2, 4, 5, 7). To the best of our knowledge, no previous reports have described a purely hemorrhagic cystic schwannoma (2, 4, 5, 7). We present a case of a purely cystic schwannoma between the vastus lateralis, and the vastus intermedius muscles resembling a hemorrhagic ganglion cyst or a chronic hematoma. This is an Open Access article distributed under the terms of the Creative Commons Attribution Non-Commercial License (http://creativecommons.org/licenses/ by-nc/3.0/) which permits unrestricted non-commercial use, distribution, and reproduction in any medium, provided the original work is properly cited. Received: December 15, 2016 Revised: March 10, 2017 Accepted: March 21, 2017