Description of a neural sheath tumor of the trigeminal nerve: immunohistochemical and electron microscopy study

Spontaneous malignant transformation of trigeminal schwannoma: consideration of responsible gene alterations for tumorigenesis-a case report

Malignant peripheral nerve sheath tumors (MPNSTs) arising from the trigeminal nerves are extremely rare (only 45 cases, including the present case, have been published) and have been reported to develop de novo from the peripheral nerve sheath and are not transformed from a schwannoma or neurofibroma. Here, we report a case of MPNSTs of the trigeminal nerve caused by the malignant transformation of a trigeminal schwannoma, with a particular focus on genetic considerations. After undergoing a near-total resection of a histologically typical benign schwannoma, the patient presented with regrowth of the tumor 10 years after the primary excision. Histopathologic and immunochemical examinations confirmed the recurrent tumor to be an MPNST. Comprehensive genomic analyses (FoundationOne panel-based gene assay) showed that only the recurrent MPNST sample, not the initial diagnosis of schwannoma, harbored genetic mutations, including NF1-p.R2637* and TP53-p.Y234H, candidate gene mutations associated with malignant transformation. Moreover, the results of reverse transcription polymerase chain reaction showed that the fusion of SH3PXD2A and HTRA1, which has been reported as one of the responsible genetic aberrations of schwannoma, was detected in the recurrent tumor. Taken together, we could illustrate the accumulation process of gene abnormalities for developing MPNSTs from normal cells via schwannomas.

Neurilemmoma of the Nasal Cavity and Paranasal Sinuses

OBJECTIVES

Neurilemmoma in the nasal cavity and paranasal sinuses is very rare. The study aimed to improve the understanding of neurilemmoma in the nasal cavity and paranasal sinuses.

MATERIALS AND METHODS

The clinical data of 10 patients with neurilemmoma in the nasal cavity and paranasal sinuses treated from January 2014 to June 2019 in our hospital were retrospectively studied.

RESULTS

There were 6 females and 4 males patients in our study. The mean age was 49.5 years (range 37-77 years), and the most common clinical symptom was unilateral nasal obstruction. The site of tumor included the nasal cavity, maxillary sinus, ethmoid sinus, and sphenoid sinus. There were 2 cases with malignant neurilemmoma. Nine patients underwent functional endoscopic sinus surgery (FESS); however, 1 patient underwent FESS combined with the lateral rhinotomy for complete resection of the tumor. Two patients with malignant neurilemmoma received postoperative radiotherapy. The mean follow-up was 3.82 years (range 2-7 years). There were no incidences of tumor recurrence during the study period.

CONCLUSIONS

Neurilemmoma in the nasal cavity and paranasal sinuses is a mainly benign tumor. Complete surgical excision by FESS is the only treatment option for neurilemmoma in the nasal cavity and paranasal sinuses; while malignant neurilemmoma needs postoperative radiotherapy.

Treatment, outcomes, and demographics in sinonasal sarcoma: a systematic review of the literature

Background

Sarcomas comprise a diverse group of soft tissue mesenchymal malignancies. The sinuses and nasal region are a relatively rare site of sarcomas.

Methods

Retrospective review of the literature on sinonasal sarcomas from 1987-2017. Data were analyzed for demographics, treatment type, stage, and histopathologic type. Kaplan-Meier analysis was used to assess and compare survival.

Results

A total of 198 cases of sinonasal sarcoma were identified and analyzed. The median age at diagnosis was 39 years. Overall 5-, 10-, and 20-year survival was 61.3%, 58.9%, and 49.1%, respectively, and disease-free 5-, 10-, and 20-year survival was 53.2%, 49.1%, and 38.3%, respectively. Lymph node metastasis was present at diagnosis in 3.0% of cases, and distant metastasis was present in 3.5% of cases. On univariate analysis T stage, overall stage, treatment type, histopathologic subtype, and presence of distant metastasis significantly affected survival. On multivariate analysis overall stage alone significantly predicted overall survival. Open vs. endoscopic surgery, total radiation dose, and presence of neck metastasis did not significantly affect survival. Combined modality treatment was associated with higher survival rates than single modality therapy.

Conclusions

Sinonasal sarcoma is a relatively rare malignancy. Lower T and overall stage, lack of distant metastasis, and multimodality therapy were associated with improved survival. Certain histopathologic subtypes were associated with poorer survival.

Electronic supplementary material

The online version of this article (10.1186/s12901-018-0052-5) contains supplementary material, which is available to authorized users.

Malignant peripheral nerve sheath tumors of the trigeminal nerve: a systematic review of 36 cases

OBJECT

Malignant peripheral nerve sheath tumors (MPNSTs) are a rare form of malignancy arising from the Schwann cells of peripheral nerves. MPNSTs of the trigeminal nerve are exceptionally rare, with only a handful of reports in the literature. These tumors are typically very aggressive, resulting in significant patient morbidity and a generally grim prognosis. Most current reports suggest that radical resection with radiation therapy offers the best benefit. In this study, the authors systematically reviewed the world English-language literature on MPNSTs of the trigeminal nerve to analyze the presentations, treatment options, and outcomes for patients with this disease.

METHODS

A literature search for MPNSTs of the trigeminal nerve confined to nonanimal, English-language articles was conducted utilizing the PubMed database, with additional cases chosen from the references of selected articles. Only cases of confirmed MPNSTs of the trigeminal nerve or its peripheral branches, based upon surgical, pathological, or radiological analysis, were included.

RESULTS

From the literature search, 29 articles discussing 35 cases of MPNSTs of the trigeminal nerve were chosen. With the addition of 1 case from their own institution, the authors analyzed 36 cases of trigeminal MPNSTs. The average age of onset was 44.6 years. These tumors were more commonly seen in male patients (77.1%). The gasserian ganglion was involved in 36.1% of the cases. Of the cases in which the nerve distribution was specified (n = 25), the mandibular branch was most commonly involved (72.0%), followed by the maxillary branch (60.0%) and the ophthalmic branch (32.0%), with 44.0% of patients exhibiting involvement of 2 or more branches. Altered facial sensation and facial pain were the 2 most commonly reported symptoms, found in 63.9% and 52.8% of patients, respectively. Mastication difficulty and diplopia were seen in 22.2% of patients, facial weakness was seen in 19.4%, and hearing loss was present in 16.7%. With regard to the primary treatment strategy, 80.6% underwent resection, 16.7% underwent radiation therapy, and 2.9% received chemotherapy alone. Patients treated with complete resection followed by postoperative radiation therapy had the most favorable outcomes, with no patients showing evidence of disease recurrence with a mean follow-up of 34.6 months. Patients treated with incomplete resection followed by postoperative radiation therapy had more favorable outcomes than patients treated with incomplete resection without radiation therapy or radiation therapy alone.

CONCLUSIONS

Trigeminal MPNSTs most commonly present as altered facial sensation or facial pain, although they exhibit a number of other clinical manifestations, including the involvement of other cranial nerves. While a variety of treatment options exist, due to their highly infiltrative nature, aggressive resection followed by radiation therapy appears to offer the greatest chance of recurrence-free survival.