Ultrastructural and immunohistochemical identification of malignant schwannoma of the skin

Optimal treatment of jugular foramen schwannomas: long-term outcome of a multidisciplinary approach for a series of 29 cases in a single institute

BACKGROUND

The goal of treatment for jugular foramen schwannomas (JFSs) is to achieve complete tumor removal with cranial nerve preservation. However, achieving this goal remains a challenge despite the advances in microsurgical techniques. The aim of this study was to determine optimal treatment strategies for JFSs based on a review of a series of 29 surgical cases in our institute.

MATERIALS AND METHODS

Between 1997 and 2013, 29 patients with JFSs underwent surgical treatment by multidisciplinary otoneurosurgical approaches. We retrospectively evaluated various clinical outcomes including the extent of tumor resection, postoperative cranial nerve deficits, and the recurrence rate. Tumor extension was classified using the Kaye and Pellet classification (KPC) system, and the extent of tumor resection was graded as gross total resection (GTR), near total resection (NTR), and subtotal resection (STR). We utilized the House-Brackmann facial nerve grading system (HBFNGS), the average pure-tone audiometry and speech audiometry (PTA/SA) tests, and the American Speech-Language-Hearing Association National Outcome Measurement System (ASHA NOMS) swallowing scale (ASHA level) for assessment of functional outcomes.

RESULTS

The extent of tumor resection was not related to the degree of immediate postoperative cranial nerve deficits. However, the surgical approach was significantly related to postoperative hearing status and immediate postoperative facial function. Also, among the ten patients who were below the level of acceptable facial function immediately postoperatively, nine patients (90%) recovered to acceptable facial function by the last follow-up. Concerning postoperative swallowing status, all 21 patients recovered swallowing function by the last follow-up. Postoperative Gamma Knife stereotactic radiosurgery (GKRS) was performed for three recurrent and seven residual tumors, and recurrence was not observed in the mean 36-month follow-up period.

CONCLUSIONS

A surgical strategy should be tailored to the individual case, and clinicians should consider the possibility of recurrence and further adjuvant treatment.

Neurofibrosarcoma of skin and subcutaneous tissues

In this report, we describe 13 cases of primary neurofibrosarcoma of the skin. The tumor presumably arises from small cutaneous nerves, is locally aggressive, and has a potential for metastasis. Characteristic histopathologic features include proliferating atypical spindle cells with slender wavy and pointed nuclei; hypocellular areas with loose, myxoid stroma; and areas of organoid organization such as palisading, whorly, storiform, and tactile body-like formations. The S-100 stain is positive in about 60% of cases. In the current series, most tumors arose in deep dermis and were grade 2 malignant lesions with a moderate degree of cytologic atypia and 2 or fewer mitoses in 10 high-power fields. Three patients died of their malignant lesion. Only two tumors metastasized. Of the 10 patients who had local recurrence, 5 had multiple recurrent lesions. Neurofibrosarcoma should be considered in the differential diagnosis of malignant tumors of the skin. A complete surgical resection of the primary tumor with adequate margins of surrounding normal-appearing tissue is advised.