Rare malignant peripheral nerve sheath tumor of vagus nerve: A case report

Abstract

Introduction: MPNST is a rare type of malignancy classified as malignant soft tissue sarcoma. One-fourth to one-half of MPNST arise in patients with neurofibromatosis type 1 (NF1) and generally involves major nerve trunks of proximal extremities and body, rarely head and neck region. Aggressive nature of the disease shows poor overall prognosis, where treatment modalities are also limited.

Presentation of case: 62-year-old otherwise healthy female underwent radical surgical treatment due to the mass of the right side of the neck. Preoperative MRI studies showed well defined partly cystic and visually malignant neoplasm of the carotid sheath in upper third of the neck. Well-defined tumor of the right vagus nerve was detected during the surgery and was excised with safe and radical margins. Further histological study confirmed MPNST diagnosis. Defect of the vagus nerve was reconstructed with a nerve grafts to maintain and improve patients quality of the life. Adjuvant radiotherapy was appointed. At one year follow-up period no evidence of disease recurrence was found. Nevertheless, patient reported significant improvement of functionality and less vagus nerve impairment symptoms.

Discussion: In this article we discuss main epidemiological data of MPNST as well as distinction of our clinical case peculiarities from data mentioned in literature.

Conclusion: MPNST are described as aggressive neoplasms with unfavorable short and long-term prognosis. Early diagnosis and radical surgical intervention not only improve patient prognosis but also allow to use additional treatment options to improve patients survival and quality of the life even in case of MPNST.

Keywords: Case report; MPNST; Nerve graft; Nerve reconstruction; Vagal nerve.

Fig. 1

MRI scan in axial plane indicating neoplasm of carotid sheath of the right side of neck. A- T1, B- T2, C- T2 STIR sequences.

Fig. 2

MRI scan indicating neoplasm of carotid sheath of the right side of neck. A- coronal plane T2 sequence, B- coronal plane T2 STIR sequence, C- sagittal plane T2 sequence.

Fig. 3

Intraoperative finding- solid and well-defined mass of the right side vagus nerve.

Fig. 4

Representative photomicrograph demonstrated MPNST. A-hematoxylin eosin staing method, magnification ×100, scale bar-50 μm. B-S-100 expression, immunohistochemical staining method, magnification ×100, scale bar-50 μm. C- Ki-67 expression, immunohistochemical staining method, magnification ×200, scale bar-100 μm; D- SOX-10 expression, immunohistochemical staining method, magnification ×200, scale bar-100 μm.

Fig. 5

Intraoperative microscopic image - vagus nerve reconstruction with sural nerve grafts.