Investigation of locoregional metastatic behavior in low-grade malignant tumors of the parotid gland

Background: The aim of the study was to investigate primary locoregional metastatic behavior in a large sample of low-grade malignant tumors of the parotid gland following surgical treatment consisting of complete parotidectomy and neck dissection. Methods: The records of all patients treated for low-grade malignant tumors of the parotid gland by complete parotidectomy and neck dissection between 2007 and 2022 were studied retrospectively. Results: 94 patients formed our study sample (50 females, 44 males, female to male ratio: 1.14). The mean age was 59 years (range 15-95 years). The mean number of lymph nodes in the specimen from complete parotidectomy was 3.33 (range: 0-12). The mean number of involved lymph nodes in the parotid gland was 0.05 (range: 0-1). The mean number of lymph nodes in the specimen from the ipsilateral neck dissection was 16.2 (range 4-42). The mean number of involved lymph nodes in the neck dissection specimen was 0.09 (range: 0-2). Comparison of T1-T2 vs. T3-T4 cases revealed no statistically significant difference concerning the tumorous involvement of the lymphatic network (chi(2) = 0.719, p = 0.396). Conclusion: Low-grade primary malignant tumors of the parotid gland are characterized by an initially low metastatic potential, which justifies conservative forms of surgical treatment.