Contralateral neck dissection in oral cavity cancers crossing midline: A look in the mirror

Introduction: Oral cavity cancer is the most common cancer in our country. In patients with oral cavity squamous cell carcinoma (OCSCC) elective neck dissection results in higher rates of overall survival and disease-free survival. Nodal metastasis in OCSCC is related to poor prognosis. Elective ipsilateral node dissection is recommended in all patients. Contralateral nodal metastasis is associated with poorer prognosis. The purpose of our study is to identify the predictors and factors associated with bilateral or contralateral nodal metastasis in oral cavity cancers reaching or crossing the midline. Materials and Methods: All patients of oral cavity cancer where the primary cancer was reaching or crossing the midline, operated during 3 years in a single institute were taken up for the study. All patients underwent surgery of primary cancer and bilateral neck dissection. Patients with truly lateral disease not approaching midline, history of any previous oncologic treatment, and recurrent cancers, and patients with two or more primaries were excluded from the study. Results: Out of 93 patients, 43% of the buccal mucosa – gingivobuccal sulcus region and 57% of the tongue – floor of mouth region. Out of 46 patients having nodal metastasis (50%), 26.8% of patients had bilateral nodal metastasis, but none had isolated contralateral nodal metastasis. On univariate and bivariate analysis, we found tumor grade, stage, site of ENE, and presence of multiple ipsilateral positive nodes were significant factors predicting contralateral nodal metastasis. Conclusion: Surgical management of the contralateral neck in oral cavity cancer is a complex issue. The simplistic approach of doing contralateral neck dissection in all oral cavity cancers when disease crosses midline is not sufficient. The presence of contralateral neck node metastasis in the absence of positive ipsilateral neck is very rare (0% in our study). There are other important clinic radiological factors such as DOI >10 mm, involvement of skin and bone, and presence of extranodal extension and location of primary tumor which also need to be considered in decision-making algorithm.