Primary neoplasms of the parapharyngeal space: diagnostic and therapeutic pearls and pitfalls

Abstract

Purpose: Parapharyngeal space neoplasms (PSNs) are rare tumors of the head and neck region. In this study, we report our institutional experience with PSNs over a 27-years period. Methods: Patients treated between 1992 and 2018 were identified through our tumor board database. Data concerning demographics, clinical presentation, disease features, treatment, complications and follow-up were obtained retrospectively. Results: In total, 48 patients were identified. Most patients had benign tumors (67.5%), with pleomorphic adenoma and schwannoma being the most frequent entities. Malignant tumors represented the remaining 32.5% of neoplasms. Concerning tissue of origin, 67.5% of neoplasms originated from salivary glands and 17.5% were neurogenic. The vast majority of PSNs required open surgical approaches (77%). The most frequent reversible and irreversible complications included paralysis of facial, vagal, and hypoglossal nerves (transient 62.5%, permanent 31.3%). Tumor recurrences occurred in 16.7% of our patients. Conclusion: Neoplasms of the parapharyngeal space (PPS) are rare. In our series, consistent with the literature, most patients had benign tumors. Fine-needle aspiration cytology (FNAC) and/or transoral biopsy in selected cases combined with radiographic imaging are helpful to plan the optimal approach (open/transoral) and extent of primary surgery. Close follow-up in malignant neoplasms is crucial to assess recurrence early. We present one of the largest recent studies on PPS tumors treated in a center. Given the low incidence of these tumors, our results contribute to the existing sparse evidence regarding the management and outcome of such tumors.