Background: Parapharyngeal space tumors with complex anatomy and diverse histology and have remained a challenging phenomenon for treating physicians. Objective: Assess the factors for selection of surgical approach and association of neurological complications with tissue of origin in parapharyngeal space tumors. Type of review: Systematic review and meta-analysis of retrospective studies in accordance with PRISMA guidelines Methods: We have conducted a comprehensive web search on Pubmed, Web of Science, EMBASE, Cochrane Library, Biomedical Literature Database (CBM) and Clinicaltrials.gov. Two researches reviewed all identified articles independently with a third reviewer for adjudication. Patient demographics and other clinicopathological characteristics were explored. Main outcome measures: Primary outcomes assessed were post-operative complications i.e. neurological and salivary, surgical approaches used and the factors used for the selection of surgical approaches. Results: The systematic review has identified 631 patients of benign parapharyngeal space tumors with neurogenic and salivary tissue histology in 13 studies with a mean age of 42.9 ± 7.76 years and a median follow-up of 40.98 ± 19.1 months. Salivary gland (50.8%) and neurogenic (49.1%) tumors were the most common histological entities. Tumor size, location, histology, deep parotid lobe involvement and proximity to great vessels or skull base were the deciding factors in selecting the surgical approach. Factors considered to select surgical approach do not seem to have a correlation with the outcome in terms of neurological sequalae (p=0.106). Neurological deficit was observed in 48% of patients with neurogenic histology (148/310) while only 13% patients with salivary tumor developed neurological deficit. The pooled RR was 2.41 (95% CI 1.80 -3.23, p=0.001). Conclusion: Neurologic complications are significantly associated with neurogenic benign tumors rather than surgical approach.

Introduction Parapharyngeal space tumors with complex anatomy and diverse histology have remained a challenging phenomenon for treating physicians. Objectives We have conducted a comprehensive web search on the PubMed, Web of Science, EMBASE, Cochrane Library, Biomedical Literature Database (CBM), and Clinicaltrials.gov databases to determine the factors that are associated with postoperative complications in parapharyngeal space tumors. Data Synthesis Two researchers reviewed all identified articles independently with a third reviewer for adjudication. Patient demographics and other clinicopathological characteristics were explored. The systematic review has identified 631 benign parapharyngeal space tumors with neurogenic and salivary tissue histology in 13 studies, with a mean age of 42.9 ± 7.76 years old and a median follow-up of 40.98 ± 19.1 months. Salivary gland (50.8%) and neurogenic (49.1%) tumors were the most common histological entities. Tumor size, location, histology, deep parotid lobe involvement, and proximity to great vessels or to the skull base were the deciding factors in selecting the surgical approach. The factors considered to select the surgical approach do not seem to have a correlation with the outcome in terms of neurological sequalae (p = 0.106). Tumors with neurogenic histology have significantly increased chances of developing neurological complication (OR 6.07; p = 0.001). Conclusion Neurologic complications are significantly associated with neurogenic benign tumors rather than surgical approach.