Results
Fourteen eligible studies were identified, including 1,780 patients, of whom 294 received ND as their sole treatment (seven studies) with 3-year OS ranging from 43.9% to 100%. 3-year DFS was reported in four studies (n=62) ranging from 42.8% to 67.0%. 5-year OS and DFS were available in three studies (n=31), ranging from 36.6% to 75.0%, and 43.6% to 67.0%, respectively. The rate of primary emergence ranged from 11.1% to 33.3% (seven studies, n=157), regional relapse from 0.0% to 50.0% (five studies, n=60), and distant metastasis from 0.0% to 3.3% (three studies, n=45). Patients undergoing ND as a sole treatment had predominantly p16 positive N1 (TNM7) disease without ECS.