title: Non-sentinel node tumor invasion in oropharyngeal and oral cancer: risk of misdiagnosis of metastasis.
abstract: CONCLUSIONS
  The existence of patients with positive non-sentinel node indicates a risk of misdiagnosis of metastasis in oropharyngeal and oral cancer.
  
  
  OBJECTIVE
  We attempted to confirm the usefulness of sentinel lymph node biopsy (SLNB) in oropharyngeal and oral cavity cancer to detect clinically occult metastases.
  
  
  METHODS
  Twenty-two patients with a mean age of 57 (SD=13) years were studied prospectively. All presented T1-T3 squamous cell carcinoma (SCC) of the oropharynx or oral cavity, and were cN0 on palpation and CT. A preoperative (24 h) lymphoscintigraphy was performed with 99mTc-labelled sulfur colloid injected around the primary tumor. Subsequently, we proceeded with tumor exeresis and detection of SLN following the procedures described in a previous paper.
  
  
  RESULTS
  We detected a total of 32 SLNs in 21 of 22 patients. Ipsilateral neck node location was observed in 18 patients and bilateral in 3. We observed 10 patients with true positive SLNs (3 patients had micrometastases), indicating occult metastases. We harvested a total of 454 nodes in our selective neck dissections, 19 of which presented metastatic invasion. We identified four patients with positive non-sentinel nodes.
authors.affiliation: Department of Otorhinolaryngology, Basurto Hospital, School of Medicine, University of the Basque Country, Gurtubay, Bilbao, Spain.
authors.forename: F
authors.initials: F
authors.lastname: Santaolalla
authors.forename: J M
authors.initials: JM
authors.lastname: Sanchez
authors.forename: C
authors.initials: C
authors.lastname: Ereño
authors.forename: A
authors.initials: A
authors.lastname: Gonzalez
authors.forename: M L
authors.initials: ML
authors.lastname: Rodriguez
authors.forename: A
authors.initials: A
authors.lastname: Sanchez
authors.forename: A
authors.initials: A
authors.lastname: Martinez
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002294:Carcinoma, Squamous Cell / Q000473:pathology*; D005260:Female; D006801:Humans; D008198:Lymph Nodes / Q000000981:diagnostic imaging; D008207:Lymphatic Metastasis / Q000175:diagnosis*; D008297:Male; D008875:Middle Aged; D009062:Mouth Neoplasms / Q000473:pathology*; D037981:Neck Dissection; D009959:Oropharyngeal Neoplasms / Q000473:pathology*; D011446:Prospective Studies; D011877:Radionuclide Imaging; D019275:Radiopharmaceuticals; D021701:Sentinel Lymph Node Biopsy; D013671:Technetium Tc 99m Sulfur Colloid
chemical_list: D019275:Radiopharmaceuticals; D013671:Technetium Tc 99m Sulfur Colloid