Abstract
BACKGROUND: Ipsilateral neck radiotherapy (INRT) is controversial in some patients with oral cavity cancer due to concern for contralateral neck failure (CNF). METHODS: A systematic review was performed and data were extracted following PRISMA guidelines. Outcomes were the rate of CNF following INRT and the rates of CNF by AJCC 7th ed. tumor and nodal staging. RESULTS: Fifteen studies consisting of 1825 patients were identified. Among the 805 patients treated with INRT, the rate of CNF was 5.7%. Patients with T4 tumors constituted 56% of all CNF cases. The rate of CNF increased by N stage (N0: 1.2%; N1: 3.8%; N2-N3: 17.4%) and was significantly higher for patients with N2-N3 than N0-N1 disease (p < 0.001). DISCUSSION: INRT is associated with an overall low risk of CNF in well-selected patients with N0-N1 disease. Patients with N2-3 and/or T4 disease should receive bilateral RT due to increased risk of CNF following INRT.