Malignant nerve sheath tumors of the head and neck: four case studies and review of the literature

Update on MR Imaging of Soft Tissue Tumors of Head and Neck

This article reviews soft tissue tumors of the head and neck following the 2020 revision of WHO Classification of Soft Tissue and Bone Tumours. Common soft tissue tumors in the head and neck and tumors are discussed, along with newly added entities to the classification system. Salient clinical and imaging features that may allow for improved diagnostic accuracy or to narrow the imaging differential diagnosis are covered. Advanced imaging techniques are discussed, with a focus on diffusion-weighted and dynamic contrast imaging and their potential to help characterize soft tissue tumors and aid in distinguishing malignant from benign tumors.

Malignant peripheral nerve sheath tumour of the oral and maxillofacial region-A systematic review

To integrate the available data published on malignant peripheral nerve sheath tumours (MPNST) of the oral and maxillofacial region. Searches in Embase, PubMed, Web of Science and Scopus were conducted for the identification of case reports/case series in English language. The risk of bias was assessed using the Joanna Briggs Institute tool. Outcomes were evaluated by Cox regression and Kaplan-Meier methods. A total of 306 articles were retrieved, 50 of which reporting 57 MPNST were included. The lesion showed a predilection for the mandible (n = 18/31.57%) of middle-aged adults (~40.5 years) with a male/female ratio of 1.1:1. The individuals were mostly symptomatic with a mean evolution time of 9.6 months. Surgical removal plus adjuvant therapy (especially radiotherapy) was the main approach (51.86%). Recurrence was reported in 39.62% of cases. Nodal and distant metastases were identified in 28.26% and 26.66% of cases, respectively. The 2-year cumulative survival rate was 55%. Independent predictors of poor survival were the presence of neurofibromatosis type 1 (p = 0.04) and distant metastases (p = 0.004). The diagnosis of MPNST is challenging due to the variety of its clinical and histopathological presentations. Local aggressiveness and the potential for metastases are common outcomes of this neoplasm.

Neurofibrosarcoma of the mandible derived from neurofibromatosis

Neurofibrosarcoma is a rare malignant neoplasm of the head and neck region and accounts for 8% to 16% of all cases. Its origin is varied and may stem from cells of the peripheral nerves, develop de novo, or result from malignant transformation of preexisting neurofibromas. Because the features of neurofibrosarcomas are heterogeneous, the data retrieved during clinical examinations are of great aid for diagnosis. In this case, owing to clinical features and the fact that the patient had neurofibromatosis type 1, the hypothesis of neurofibrosarcoma was promptly established. The final diagnosis was confirmed by associating clinical, imaging, and pathological data. After the treatment, the patient has been followed up for 10 years, with no evidence of recurrence.

Malignant peripheral nerve sheath tumor of the parotid gland

Malignant peripheral nerve sheath tumor (MPNST) refers to spindle cell sarcomas arising from or separating in the direction of cells of the peripheral nerve sheath. The MPNST of the parotid gland is an extremely rare tumor, usually having a poor prognosis, and only a few cases been described in the literature. In this article, we report the diagnostic and therapeutic challenges related to a new case of MPNST of the parotid. Diagnosis was made based on clinical, imaging (computed tomography scan), histologic, and immunohistochemistry findings. Despite comprehensive treatment--complete surgical resection and radiotherapy--the tumor displayed a highly aggressive course.

Sporadic Multifocal Malignant Peripheral Nerve Sheath Tumor-A Rare Presentation: Multifocal MPNST

Malignant peripheral nerve sheath tumors(MPNST) are uncommon neoplasms with an incidence of 0.001% in general population. Multifocality is a rare manifestation of MPNST . A case of a 65 year old patient who presented with multiple swellings involving the neck, extremity and back without associated neurofibromatosis is reported for its rarity of presentation.. Diagnosis was made by FNAC and confirmed by peroperative findings and histopathology.

Malignant peripheral nerve sheath tumour of the paranasal sinuses and the anterior skull base

BACKGROUND

Malignant peripheral nerve sheath tumours (MPNSTs) are highly aggressive neoplasms with a marked propensity for local recurrence and metastatic spread. The management of MPNSTs continues to challenge pathologists and surgeons. As MPNSTs of the paranasal sinuses and the skull base are rare, prognostic factors and treatment modalities have not been consistently identified.

PATIENTS AND METHODS

We present a case of MPNST of the anterior skull base and provide an overview of all MPNSTs reported since 1970, in which the tumour location was the anterior skull base or the paranasal sinuses.

RESULTS

Literature review revealed 33 well-documented cases of MPNSTs in this anatomic location. These cases were analysed with emphasis on age, gender, affected site, therapy, outcome, presence of neurofibromatosis, local recurrence and metastases.

CONCLUSIONS

Despite multimodal therapy and advances in surgical techniques, the prognosis of MPNST located in the paranasal sinuses and the anterior skull base remains dismal. Outcome is mainly a function of local control by surgical resection. Adjuvant radiochemotherapy has shown no benefit. It may therefore be advisable to abstain from radiochemotherapy in order to improve chances for surgical intervention in case of recurrent disease. Close follow-up investigations are indispensable.

FDG PET and PET/CT for the detection of the primary tumour in patients with cervical non-squamous cell carcinoma metastasis of an unknown primary

In patients with a neck metastasis from an unknown primary with non-squamous cell cancer (non-SCC) histology, the primary is often located outside the head and neck area. We retrospectively evaluated 326 patient records and found 14 patients with non-SCC neck lymph node metastasis from an unknown primary undergoing whole body F-18-fluorodeoxyglucose (FDG) positron emission tomography (PET) with or without coregistered computed tomography (PET/CT). The PET or PET/CT findings were verified by pathological work-up, additional imaging tests, and clinical follow-up. PET detected pathological FDG uptake suspicious for the primary in eight patients. PET or PET/CT findings were true positive in seven patients, true negative in 4, false positive in 1, and false negative in two patients. In one patient PET/CT revealed a synchronous ovarian carcinoma. The results suggest that whole body imaging with FDG PET and PET/CT can be useful to identify unknown primaries of non-SCC origin. However, the work-up of patients undergoing PET or PET/CT in our study was very heterogeneous and the primary was more likely found in patients without extensive imaging before PET scanning. Further studies should evaluate if the histology of a neck nodal metastasis should influence the choice of the imaging method and the role of PET and PET/CT imaging for the work up of patients with a non-SCC neck lymph node metastasis of an unknown primary.

Malignant peripheral nerve sheath tumor of the parotid gland

Malignant peripheral nerve sheath tumor (MPNST) has been defined as any malignant tumor arising from or differentiating toward cells of the peripheral nerve sheath. We treated a case of MPNST arising from the right parotid gland that showed a highly aggressive course. We reviewed the English-language literature published since 1990 and found 142 cases of head and neck MPNST reported within the past 13 years. The results of the review suggested that MPNSTs may arise from any organs of the head and neck. Immunohistochemical analysis of various neural markers plays a significant role in the evaluation of the histologic diagnosis. Curative treatment based on radical resection of MPNSTs of head and neck origin is more difficult than treatment of MPNSTs of other origins.

Malignant peripheral nerve sheath tumour metastasising to the parotid gland

Two rare cases of metastases from malignant peripheral nerve sheath tumours (MPNST) of the head and neck are described. The initial lesions were superficial, but despite early diagnosis and complete excision, they metastasised to the ipsilateral parotid gland. Both underwent further complete excision and neither metastatic lesion showed progression in grade. One patient is alive, however, the other died of widespread metastases. There are no other reported cases of these sarcomas in the head and neck metastasising to the parotid gland.