Does three-dimensional intraglandular location predict malignancy in parotid tumors?

Tumors arising within the parotid encompass a heterogeneous mix of benign and malignant neoplasms and other tissue growths. The purpose of this study was to determine the association between the location of intraparotid masses and the risk of malignancy. A retrospective cohort study was performed of patients diagnosed with parotid tumors following open tumor excision. The primary predictor variable was the location of the epicenter of the tumor in three-dimensional space, as determined from preoperative imaging. Other variables were patient demographics and clinical parameters. The primary outcome variable was the final histopathologic diagnosis of a benign or malignant process. A χ² analysis was performed to test for any significant associations between demographic, clinical, and radiographic factors in relation to the outcome, and backwards stepwise logistic regression analysis was used to control for variables. Both increasing age (P = 0.002) and the presence of local pain (P = 0.020) were associated with malignancy. Tumors located anterior to the posterior border of the retromandibular vein had 2.18 times higher odds of malignancy (95% confidence interval 1.13-4.21; P = 0.020). Multivariate regression analysis suggested that patient age, the presence of pain, and tumor location anterosuperiorly and superoinferiorly could all assist in determining the odds of malignancy.