title: Level IIB lymph node metastasis in oropharyngeal squamous cell carcinoma.
abstract: OBJECTIVE
  To determine the incidence of level IIB lymph node metastasis in patients with oropharyngeal squamous cell carcinoma (OPSCC) and to evaluate the necessity of level IIB dissection for elective and therapeutic neck dissections.
  
  
  METHODS
  Retrospective cohort study.
  
  
  METHODS
  Patients with OPSCC (N = 348) were surgically managed at our institution from 2004 through 2010. Neck dissection specimens were reviewed by a pathologist, and level IIB metastases were analyzed with respect to clinical and pathologic data.
  
  
  RESULTS
  Level IIB lymph node metastases were present in 2.5% and 25% of elective and therapeutic neck dissections, respectively. Level IIA metastasis, clinical tumor stage, clinical nodal stage, extracapsular spread, and primary tumor location in the tonsil were significantly associated with level IIB metastasis.
  
  
  CONCLUSIONS
  This study uniquely demonstrated a statistically significant association between clinical tumor stage and tonsil subsite with level IIB metastasis in OPSCC. Considering the predicted incidence of nodal metastasis, we conclude that level IIB neck dissection can be omitted in early stage (T1 or T2) clinically node negative (cN0) OPSCC. In patients with a cN0 neck and advanced OPSCC (T3 or T4), primary tumor in the tonsil, or ipsilateral clinically node positive (cN(+) ) and contralateral cN0 neck, level IIB dissection should be considered. Level IIB dissection should be performed routinely in patients with cN(+) OPSCC.
authors.affiliation: Department of Otorhinolaryngology-Head and Neck Surgery, Mayo Clinic, Rochester, Minnesota, U.S.A.
authors.forename: Brian C
authors.initials: BC
authors.lastname: Gross
authors.forename: Steven M
authors.initials: SM
authors.lastname: Olsen
authors.forename: Jean E
authors.initials: JE
authors.lastname: Lewis
authors.forename: Jan L
authors.initials: JL
authors.lastname: Kasperbauer
authors.forename: Eric J
authors.initials: EJ
authors.lastname: Moore
authors.forename: Kerry D
authors.initials: KD
authors.lastname: Olsen
authors.forename: Daniel L
authors.initials: DL
authors.lastname: Price
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002294:Carcinoma, Squamous Cell / Q000556:secondary* / Q000601:surgery*; D015331:Cohort Studies; D005260:Female; D006801:Humans; D008207:Lymphatic Metastasis; D008297:Male; D008875:Middle Aged; D009333:Neck; D037981:Neck Dissection / Q000379:methods*; D009959:Oropharyngeal Neoplasms / Q000473:pathology* / Q000601:surgery*; D012189:Retrospective Studies
keywords: Level IIB; oropharynx; squamous cell carcinoma