Oral Squamous Cell Carcinoma with Metastasis to the Parotid Lymph Node

Objective: To increase the awareness of oral squamous cell carcinoma (OSCC) metastasis to the parotid region and the characteristics of these cases, and to evaluate the outcomes and provide treatment suggestions. Methods: A retrospective study was conducted among the OSCC patients with metastasis to the parotid gland at the Peking University School and Hospital of Stomatology from 2000 to 2015. The demographic data and the medical records including primary tumour, treatment protocol, follow-up information and outcomes were collected and analysed. Results: A total of 10 patients with parotid metastasis (out of 1358 OSCC patients) were included in the study. The incidence of parotid metastasis was relatively low (0.74%). All the cases were poorly differentiated (Grade II/III) and the primary sites were in an advanced stage (T3/4). Parotid metastasis occurred frequently following neck dissection and radiotherapy, and the inferior parotid lymph nodes were most commonly involved. Surgery and radiotherapy were mainly salvage protocols for parotid metastasis. The 5-year survival rate of these patients was 38.9% by the Kaplan-Meier method. Conclusion: OSCC has the potential to metastasise into the parotid lymph nodes. The salvage rate and prognosis were relatively poor. Removing of the parotid tail along with the neck dissection is recommended for OSCC patients. Keywords: oral squamous cell carcinoma, parotid lymph node, metastasis