Factors influencing contralateral neck metastasis in oral squamous cell carcinoma

Background: Neck lymph node metastasis is the most critical factor influencing survival and prognosis of oral squamous cell carcinoma (OSCC). The risk factors for contralateral neck metastasis are still controversial. Purpose: To identify the risk factors of contralateral neck metastasis of OSCC. Methods: The 683 previously untreated OSCC patients managed at the China Medical University Hospital from January 1997 to December 2006 were reviewed. We statically analyzed the risk factors potentially related to contralateral neck lymph node metastasis. Results: Mouth floor invasion and midline crossing tumors were statistically significant for the presence of pretreatment cN2c. Midline-crossing tumors had statistically significant impact on the presence of pathologic contralateral neck lymph node metastasis (pN2c). Mouth floor invasion and poorly differentiated tumor showed statistically significant impact on contralateral neck relapse for OSCC patients who underwent only ispilateral neck dissection. Poorly differentiated tumor showed statistically significant impact on contralateral neck relapse for patients with contralateral neck dissection. Conclusion: Mouth floor invasion, midline crossing tumors, poorly differentiated tumors had a high risk in contralateral neck metastasis.