The development of a clinical algorithm for the diagnosis of tumours in the parapharyngeal space. A systematic review

Parapharyngeal space (PPS) is defined as a deep space, located around the upper pharynx, in the shape of an inverted pyramid. Primary tumours in this region are rare, accounting for 0.5% of head and neck neoplasms, and most are benign. The objective of this study is to propose a new study algorithm based on a systematic review and our experience. A cross-sectional and analytical study was carried out through review of the clinical records of our hospital. Patients with tumours of the parapharyngeal space operated from January 2010 to December 2019 and a systematic review of Pubmed studies from the last 5years were included. We considered clinical signs, diagnostic methods, presumptive diagnosis and histopathological findings. Statistical analysis was performed with STATA v.14 software. 53 of our cases and 1392 from the review were included. The clinical algorithm showed a sensitivity of 76.4% and a specificity of 96.3%, with an AUC of 0.57 for diagnosis. Complementary radiological examinations are essential in the topographic diagnosis of the tumour. Angio-MRI links the tissue of origin of the tumours and provides the highest diagnostic certainty. FNA has some disadvantages in PPS, but it is useful in some patients. The proposed algorithm contributes to obtaining excellent results in the management of these tumours because it turned out to be effective in diagnosis, and this enables improved surgical planning.