A case report on malignant peripheral nerve sheath tumor of vagus nerve: A diagnostic challenge

Malignant Peripheral Nerve Sheath Tumor (MPNST) is a rare, aggressive neoplasm with an incidence of 0.001 % and a poor prognosis. Diagnosis is particularly challenging due to its nonspecific clinical, histopathological, and radiological features, often leading to misclassification as a benign lesion. We present the case of a 24-year-old male with a progressively enlarging left-sided neck mass, accompanied by hoarseness, dysphagia, and headaches. Imaging suggested a benign peripheral nerve sheath tumor, such as a schwannoma, and an incisional biopsy further supported this impression. However, the final excisional biopsy unexpectedly confirmed MPNST of the vagus nerve. This highlights the limitations of current diagnostic techniques in distinguishing MPNST from benign mimics and underscores the critical need for a multimodal diagnostic approach, integrating advanced imaging techniques and immunohistochemistry, to improve early and accurate detection of MPNST. Given the tumor’s aggressive nature and high risk of recurrence, early identification is essential for optimizing treatment outcomes.