• Investigative Magnetic Resonance Imaging
• /
• v.21 no.3
• /
• pp.177-182
• /
• 2017

Schwannomas are benign nerve sheath tumors that are typically located in soft tissue. Occasionally, schwannomas involve osseous structures. These intraosseous schwannomas are generally benign neoplasms that account for less than 0.2% of primary bone tumors. Schwannomas are very rarely observed in long bones. We present a case of a schwannoma affecting the proximal femur with a coincident subchondral fracture of the femoral head. A 38-year-old-male presented with left hip pain without deteriorating locomotor function. Plain film radiographs displayed a lobulating contoured lesion within the intertrochanteric portion of the femur. The magnetic resonance imaging (MRI) scans showed a tumor occupying the intertrochanteric region. Diffuse bone marrow edema, especially in the subchondral and head portions of the femur that was possibly due to the subchondral insufficiency fracture was also noted. The lesion was surgically excised and bone grafting was performed. Histologically, there was diffuse infiltrative growth of the elongated, wavy, and tapered cells with collagen fibers, which are findings that are characteristic of intraosseous schwannoma. Although very rare, intraosseous schwannoma should be included in the differential diagnosis of radiographically benign-appearing, non-aggressive lesions arising in the femur. The concomitant subchondral fracture of the femoral head confounded the correct diagnosis of intraosseous schwannoma in this case.

• Archives of Craniofacial Surgery
• /
• v.16 no.2
• /
• pp.67-72
• /
• 2015

Background: A schwannoma is a benign, slow-growing peripheral nerve sheath tumor that originates from Schwann cells. Orbital schwannomas are rare, accounting for only 1% of all orbital neoplasms. In this study, we retrospectively review orbital schwannomas and characterize clinical, radiologic, and histologic features of this rare entity. Methods: A retrospective review was performed to identify patients with histologically confirmed orbital schwannoma, among a list of 437 patients who had visited our hospital with soft tissue masses within the orbit as the primary presentation between 2010 and 2014. Patient charts and medical records were reviewed for demographic information, relevant medical and family history, physical examination findings relating to ocular and extraocular sensorimotor function, operative details, postoperative complications, pathologic report, and recurrence. Results: Five patients (5/437, 1.1%) were identified as having histologically confirmed orbital schwannoma and underwent complete excision. Both computed tomography (CT) and magnetic resonance imaging (MRI) studies were not consistent in predicting histologic diagnosis. There were no complications, and none of the patients experienced significant scar formation. In two cases, patients exhibited a mild postoperative numbness of the forehead, but the patients demonstrated full recovery of sensation within 3 months after the operation. None of the five patients have experienced recurrence. Conclusion: Orbital schwannomas are relatively rare tumors. Preoperative diagnosis is difficult because of its variable presentation and location. Appropriate early assessment of orbital tumors by CT or MRI and prompt management is warranted to prevent the development of severe complications. Therefore, orbital schwannomas should be considered in the differential diagnosis of slow-growing orbital masses.

• Clinical and Experimental Pediatrics
• /
• v.57 no.9
• /
• pp.410-415
• /
• 2014

Purpose: Neurofibromatosis 1 (NF1) is an autosomal dominant condition caused by an NF1 gene mutation. NF1 is also a multisystem disorder that primarily affects the skin and nervous system. The goal of this study was to delineate the phenotypic characterization and assess the NF1 mutational spectrum in patients with NF1. Methods: A total of 42 patients, 14 females and 28 males, were enrolled in this study. Clinical manifestations and results of the genetic study were retrospectively reviewed. Results: Age of the patients at the time of NF1 diagnosis was $15.8{\pm}14.6$ years (range, 1-62 years). Twelve patients (28.6%) had a family history of NF1. Among the 42 patients, $Caf\acute{e}$-au-lait spots were shown in 42 (100%), neurofibroma in 31 (73.8%), freckling in 22 (52.4%), and Lisch nodules in seven (16.7%). The most common abnormal finding in the brain was hamartoma (20%). Mental retardation was observed in five patients (11.9%), seizures in one patient (2.4%), and plexiform neurofibromas (PNFs) in four patients (9.5%). One patient with PNFs died due to a malignant peripheral nerve sheath tumor in the chest cavity. Genetic analysis of seven patients identified six single base substitutions (three missense and three nonsense) and one small deletion. Among these mutations, five (71.4%) were novel (two missense mutations: p.Leu1773Pro, p.His1170Leu; two nonsense mutations: $p.Arg2517^*$, $p.Cys2371^*$; one small deletion: $p.Leu1944Phefs^*6$). Conclusion: The clinical characteristics of 42 Korean patients with NF1 were extremely variable and the mutations of the NF1 gene were genetically heterogeneous with a high mutation-detection rate.