[Solitary tumors of the vagus nerve in the carotid sulcus: neurofibroma and schwannoma. Apropos of 2 cases].

Neurinoma of the vagus is a rare disease (less than a hundred cases published) and even more exceptional when it develops in the carotid cervical sulcus. Indeed, nevous tumors of the neck are usually situated in a high position, in the lateo-pharyngeal space. Clinical diagnosis is difficult: a chronical enlarged lymph node is the usual suggestion. Nevertheless, two signs, albeit inconsistent are very important: cough and bradycardia on palpation of the tumefaction. Enucleation, when possible, is the best procedure for exeresis, leaving the recurrent fibers intact. But in most cases, the tumor cannot be separated from the nervous fibers and the vagus nerve must be severed at both ends. This results in definitive paralysis of the homolateral vocal cord. Microscopically, it is not always easy to distinguish between neurofibroma and schwannoma because both tumors share a common cytogenetic origin and many intermediary forms are found. Only electronic microscopy can solve litigious cases. The importance of this distinction is not only speculative, a schwannoma assumes a solitary course but a neurofibroma may belong to Recklinghausen's disease. Both schwannoma and the rare solitary neurofibroma of the cervical portion of the vagus nerve can be surgically removed, their prognosis is favorable. nervous tumors of the neck in Recklinghausen's Disease must not be operated on account of possible aggravation.