title: Elective Neck Dissection vs Observation in Early-Stage Squamous Cell Carcinoma of the Oral Tongue With No Clinically Apparent Lymph Node Metastasis in the Neck: A Systematic Review and Meta-analysis.
abstract: The elective management of no clinical or radiologic evidence of lymph node metastasis in the neck (cN0) in early stage T1-T2 oral tongue squamous cell carcinoma (OTSCC) has been the subject of much debate during the past 3 decades and continues to be controversial.
  
  
  
  To systematically review the literature and carry out a meta-analysis of studies that compared elective neck dissection (END) with observation in patients with early-stage T1-T2 OTSCC and cN0 neck.
  
  
  
  The MEDLINE, Scopus, Google scholar, and Cochrane databases were systematically searched for articles published between January 1, 1970, and June 1, 2015. Search terms used were squamous cell carcinoma, oral tongue, mobile tongue, T1, T2, early stage, elective neck dissection, no neck treatment, observation, wait and watch, node-negative neck, and N0 neck.
  
  
  
  Controlled clinical trials, prospective and retrospective cohorts, case-control studies, and case series that compared END with observation in patients with early-stage T1-T2 OTSCC who had no clinical or radiologic evidence of lymph node metastasis to the neck were eligible for inclusion in this meta-analysis. All patients included had a histopathologic diagnosis of SCC and at least 6 months of follow-up. Regional (neck) nodal recurrence, overall survival (OS), and disease-specific survival (DSS) were tested.
  
  
  
  Four researchers independently extracted information on population characteristics, outcomes of interest, and study design. Discrepancies were resolved by consensus. Fixed effects were used to determine hazard ratios (HRs) and odds ratio (ORs) were used for studies including samples without substantial heterogeneity; random effects were evaluated for samples with significant heterogeneity.
  
  
  
  A total of 20 retrospective and 3 prospective randomized studies that met the inclusion criteria, with a total of 3244 patients, were included in the meta-analysis The results showed that END significantly reduced risk of regional recurrence (random-effects model: OR, 0.32; 95% CI, 0.22-0.46; P < .001) and improved DSS (fixed-effects model: HR, 0.49; 95% CI, 0.33-0.72; P < .001) compared with management by observation. However, END did not significantly improve OS (random-effects model: HR, 0.71; 95% CI, 0.41-1.22; P = .21).
  
  
  
  The findings of this systematic review and meta-analysis indicate that END can significantly reduce the rate of regional nodal recurrence and improve DSS in patients with cT1T2N0 OTSCC.
authors.affiliation: Department of Otolaryngology-Head and Neck Surgery and Maxillofacial Surgery, Tel-Aviv Sourasky Medical Center, Sackler School of Medicine, Tel-Aviv, Israel.
authors.forename: Sara
authors.initials: S
authors.lastname: Abu-Ghanem
authors.affiliation: Department of Otolaryngology-Head and Neck Surgery and Maxillofacial Surgery, Tel-Aviv Sourasky Medical Center, Sackler School of Medicine, Tel-Aviv, Israel.
authors.forename: Moshe
authors.initials: M
authors.lastname: Yehuda
authors.affiliation: Department of Otolaryngology-Head and Neck Surgery and Maxillofacial Surgery, Tel-Aviv Sourasky Medical Center, Sackler School of Medicine, Tel-Aviv, Israel.
authors.forename: Narin-Nard
authors.initials: NN
authors.lastname: Carmel
authors.affiliation: Faculty of Management, Tel-Aviv Sourasky Medical Center, Sackler School of Medicine, Tel-Aviv University, Tel-Aviv, Israel.
authors.forename: Moshe
authors.initials: M
authors.lastname: Leshno
authors.affiliation: Department of Otolaryngology-Head and Neck Surgery and Maxillofacial Surgery, Tel-Aviv Sourasky Medical Center, Sackler School of Medicine, Tel-Aviv, Israel.
authors.forename: Avraham
authors.initials: A
authors.lastname: Abergel
authors.affiliation: Department of Radiation Oncology, Tel-Aviv Sourasky Medical Center, Sackler School of Medicine, Tel-Aviv University, Tel-Aviv, Israel.
authors.forename: Orit
authors.initials: O
authors.lastname: Gutfeld
authors.affiliation: Department of Otolaryngology-Head and Neck Surgery and Maxillofacial Surgery, Tel-Aviv Sourasky Medical Center, Sackler School of Medicine, Tel-Aviv, Israel.
authors.forename: Dan M
authors.initials: DM
authors.lastname: Fliss
mesh_terms: D002294:Carcinoma, Squamous Cell / Q000401:mortality / Q000473:pathology*; D018572:Disease-Free Survival; D006801:Humans; D037981:Neck Dissection; D009364:Neoplasm Recurrence, Local / Q000517:prevention & control; D014062:Tongue Neoplasms / Q000401:mortality / Q000473:pathology*; D057832:Watchful Waiting