Primary parapharyngeal tumours: a review of 21 cases

The diagnostic and therapeutic procedures performed in a series of patients with primary parapharyngeal space (PPS) tumours treated at the ENT Departments of San Giovanni Bosco Hospital, Turin, and of the Pugliese-Ciaccio Hospital, Catanzaro, Italy, in the period 2001-2010 are evaluated.

The retrospective review included 20 patients, 11 male and 9 female, average age of 41 years operated on for 21 primary PPS tumours. The most common tumours found were neurogenic neoplasms, while those of salivary origin were the next most common.

There were 14 paragangliomas (7 originating from carotid glomus, 5 from vagal and 2 from tympanicum), 1 sympathetic chain schwannoma and 6 pleomorphic adenomas. All the tumours were benign in nature and gave rise to few signs or symptoms. Patients underwent preoperative computed tomography (CT) scan or magnetic resonance imaging (MRI) or both. Most contrast-enhanced masses were submitted to some type of angiography. Most of the surgeries were planned through imaging alone, as preoperative fine needle aspiration (FNA) biopsy was performed only in six cases. Four different approaches were adopted for tumour removal: transcervical, transcervical/transparotid, cervical-transparotid-transmandibular and infratemporal fossa approach. There was no operative mortality, though neurologic morbidity was significant. Follow-up, extended to a maximum of 11 years, did not reveal any recurrences. In conclusion, neurogenic tumours may be the most common of PPS masses. Surgery is the mainstay treatment and external approaches offer the potential for satisfactory tumour resection. Of such external approaches, transcervical and cervical/transparotid are the most often used in benign forms.

The number of perioperative complications encountered in this series confirms the difficulty of performing surgery in this complex area, even in benign cases. The chances of avoiding vascular damage and saving the trunks or most of the nerve fibres involved depend not only on the skill and experience of the surgeon but also on the anatomy of the lesion, the type of connection between the tumour and the nerve from which it originates and the distribution of neural fibres in or around the tumour mass.