title: Lymph Node Yield as a Predictor of Survival in Pathologically Node Negative Oral Cavity Carcinoma.
abstract: OBJECTIVE
  Even after a pathologically node-negative (pN0) neck dissection for oral cavity squamous cell carcinoma (SCC), patients may develop regional recurrence. In this study, we (1) hypothesize that an increased number of lymph nodes removed (lymph node yield) in patients with pN0 oral SCC predicts improved survival and (2) explore predictors of survival in these patients using a multivariable model.
  
  
  METHODS
  Case series with chart review.
  
  
  METHODS
  Administrative database analysis.
  
  
  METHODS
  The SEER database was queried for patients diagnosed with all-stage oral cavity SCC between 1988 and 2009 who were determined to be pN0 after elective lymph node dissection. Demographic and treatment variables were extracted. The association of lymph node yield with 5-year all-cause survival was studied with multivariable survival analyses.
  
  
  RESULTS
  A total of 4341 patients with pN0 oral SCC were included in this study. The 2 highest lymph node yield quartiles (representing >22 nodes removed) were found to be significant predictors of overall survival (22-35 nodes: hazard ratio [HR] = 0.854, P = .031; 36-98 nodes: HR = 0.827, P = .010). Each additional lymph node removed during neck dissection was associated with increased survival (HR = 0.995, P = .022).
  
  
  CONCLUSIONS
  These data suggest that patients with oral SCC undergoing elective neck dissection may experience an overall survival benefit associated with greater lymph node yield. Mechanisms behind the demonstrated survival advantage are unknown. Larger nodal dissections may remove a greater burden of microscopic metastatic disease, diminishing the likelihood of recurrence. Lymph node yield may serve as an objective measure of the adequacy of lymphadenectomy.
authors.affiliation: School of Medicine, University of California San Diego, La Jolla, California, USA alemieux@ucsd.edu.
authors.forename: Aaron
authors.initials: A
authors.lastname: Lemieux
authors.affiliation: School of Medicine, University of California San Diego, La Jolla, California, USA.
authors.forename: Suraj
authors.initials: S
authors.lastname: Kedarisetty
authors.affiliation: School of Medicine, University of California San Diego, La Jolla, California, USA.
authors.forename: Sharat
authors.initials: S
authors.lastname: Raju
authors.affiliation: Division of Head and Neck Surgery, University of California San Diego, La Jolla, California, USA.
authors.forename: Ryan
authors.initials: R
authors.lastname: Orosco
authors.affiliation: Division of Head and Neck Surgery, University of California San Diego, La Jolla, California, USA.
authors.forename: Charles
authors.initials: C
authors.lastname: Coffey
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002294:Carcinoma, Squamous Cell / Q000401:mortality* / Q000473:pathology* / Q000601:surgery; D005260:Female; D006801:Humans; D008197:Lymph Node Excision; D008207:Lymphatic Metastasis; D008297:Male; D008875:Middle Aged; D009062:Mouth Neoplasms / Q000401:mortality* / Q000473:pathology* / Q000601:surgery; D037981:Neck Dissection; D011237:Predictive Value of Tests; D018426:SEER Program; D016019:Survival Analysis
keywords: SEER; head and neck; lymph node; lymph node yield; neck dissection; oral cavity; squamous cell carcinoma; surgical outcomes