Tumor, host and surgery related factors predisposing to cranial nerve deficits after surgical treatment of parapharyngeal space tumors

PROPOSE: Identification of relevant features acquired on preoperative evaluation of parapharyngeal space (PPS) tumors or related to the performed surgical approach that are predictive of the most important complication of surgical treatment of these tumors, cranial nerve palsy. METHODS: This was a retrospective analysis of 68 patients with PPS tumors treated with surgical resection in a tertiary referral center from 2009 to 2019. The preoperative clinical symptoms, age, sex, tumor size, location, histopathological type, surgical approach, radical resection, intraoperative bleeding and the occurrence of complications were collected, evaluated and compared. RESULTS: Cross-table and chi-square test results revealed that cranial nerve deficits were more common in neurogenic tumors than in other types, including malignant tumors (χ(2) = 6.118, p = 0.013); the cervical approach was selected more often for neurogenic tumors (χ(2) = 14.134, p < 0.001); neurogenic tumors were more frequently removed intracapsularly (χ(2) = 6.424, p = 0.011); and neurogenic tumors were more likely to be located in the poststyloid area (χ(2) = 17.464, p < 0.001). The two-sample t test revealed a significant correlation between age and the prevalence of cranial nerve complications (t = 2.242, p = 0.031). The mean age in the group of patients with cranial nerve palsy was 45.89 years, and that of the group without complications was 54.69 years. The results of logistic regression confirmed that the risk of nerve deficits was almost 8 times higher for neurogenic tumors (OR = 7.778, p = 0.01). None of the other analyzed variables related to tumor or surgery was significantly correlated with an increased risk of cranial nerve dysfunction. CONCLUSION: Surgical resection of tumors other than neurogenic tumors of the PPS reveals no significant risk for permanent neural dysfunction. Tumor size also had no significant effect on the risk of postoperative nerve palsy.