The role of imaging in isolated benign peripheral nerve tumors: A practical review for surgeons

Diagnostic and management considerations in incidental common peroneal intraneural haemangioma

Intraneural haemangiomas are rare tumours that can affect peripheral nerves. We describe a case of a 10-year-old female with an incidental finding of a common peroneal nerve lesion following knee injury. MRI demonstrated avid heterogeneous enhancement and peri-lesional oedema, and an open biopsy was performed revealing haemangioma on histopathological analysis. The patient was managed with observation and remains intact at 24-month follow-up.

Predictive factors of postoperative deficit and functional outcome after surgery for upper limb schwannomas: Retrospective study of 21 patients

Schwannomas are the most frequent benign tumors of the peripheral nerves. Tumor enucleation is the traditional surgical treatment. The incidence of neurological complications after surgery varies and predictive factors for these complications are not clearly defined. The aim of this study was to find predictive factors of postoperative neurological deficit after surgical treatment of schwannomas of the upper limb. Twenty-four schwannomas removed from 21 patients were analyzed retrospectively. The patients' mean age was 45.4years and the mean follow-up was 64.4months. Clinical parameters studied were age, gender, nature of preoperative symptoms, duration of symptoms, type of surgery performed, tumor location and size, nerve involved, QuickDASH and DN4 scores. Postoperative neurological deficits occurred in 14 patients (67%), with 11 having a sensory deficit and 7 a motor weakness. Eleven did not exist before surgery (6 sensory, 5 motor). In the postoperative deficit subgroup, 6 schwannomas involved the brachial plexus, 4 the ulnar nerve, and 4 the median nerve. All patients who had a fascicular resection because tumor enucleation was not feasible were in the postoperative deficit subgroup. Ten patients had either unchanged or worse QuickDASH and/or DN4 scores after surgery. Surgical treatment of schwannomas can lead to postoperative complications. Although none of our findings were statistically significant, advanced age, large tumor size, more than 16months between the first symptoms and surgery, and brachial plexus location seem to be more frequently observed in those with a postoperative neurological deficit.

Atypical schwannoma of the median nerve. A case report

Schwannomas of the hand are very rare tumors and represent less than 3% of all soft tissue tumors in the hand. These tumors share clinical, epidemiological and imaging characteristics with the other soft tissue and peripheral nerve tumors; thus, it can be difficult to make a preoperative diagnosis. Here we report the case of a 48-year-old woman who presented with a schwannoma arising from the palmar branch of the median nerve. The tumor measured 54 × 41 x 52 mm and was located in the thenar eminence. The first hypothesis was a vascular tumor. After surgery and histological analysis, the final diagnosis of an atypical schwannoma was established. The presence of shared immunohistochemical characteristics with cellular histiocytoma and myoepithelial tumors forced us to adopt an aggressive follow-up protocol. As of the last follow-up at 9 years, the patient had good clinical outcomes and no recurrence. This case highlights the difficulties encountered in clinical practice to diagnose such tumors.

Six cases of sporadic schwannomatosis: Topographic distribution and outcomes of peripheral nerve tumors

The diagnosis of schwannomatosis is often overestimated and is based on the existence of multiple peripheral nerve tumors composed exclusively of schwannomas, in the absence of clinical signs of neurofibromatosis type 2 (NF2). Sporadic forms are much more frequent than familial forms. The objective of this study was to describe the distribution of peripheral nerve tumors and investigate the outcomes of schwannomas in the context of sporadic schwannomatosis. We conducted a retrospective study of patients who fulfilled clinical diagnostic criteria for sporadic schwannomatosis. Six patients were reviewed with a mean follow-up of 38.5months (27-60months). Patients' demographic, clinical, radiographic, and pathologic data were extracted. All patients underwent slit-lamp examination, enhanced brain magnetic resonance imaging (MRI) and a spinal MRI. Enucleation that preserved nerve continuity was performed in symptomatic patients. On average, patients were 36years of age at the time of diagnosis with no sex predominance. The topographic distribution of the peripheral nerve tumors was always unilateral and most frequently targeted the upper limb. In four cases, the tumors involved the same peripheral nerve exclusively. The average number of nerve tumors observed per patient was 4.7 (2-8). The outcome after enucleation was marked by the systematic appearance of new tumors. After enucleation, no recurrence or malignant transformation was observed at the final follow-up. There was no transition to a NF2 configuration. The absence of neurofibroma and NF2 criteria makes schwannomatosis a diagnosis of exclusion. While a good prognosis can be expected following enucleation, two risks related to neurofibromatosis type 3 (NF3) are worth monitoring: the transition to NF2, particularly in young patients, and the appearance of new tumors.