title: Using endobronchial ultrasound features to predict lymph node metastasis in patients with lung cancer.
abstract: OBJECTIVE
  Reliable staging of the mediastinum determines TNM classification and directs therapy for non-small cell lung cancer (NSCLC). Our aim was to evaluate predictors of mediastinal lymph node metastasis in patients undergoing endobronchial ultrasound (EBUS).
  
  
  METHODS
  Patients with known or suspected lung cancer undergoing EBUS for staging were included. Lymph node radiographic characteristics on chest CT/PET scan and ultrasound characteristics of size, shape, border, echogenicity, and number were correlated with rapid on-site evaluation (ROSE) and final pathology. Logistic regression (estimated with generalized estimating equations to account for correlation across nodes within patients) was used with cancer (vs normal pathology) as the outcome. ORs compare risks across groups, and testing was performed with two-sided α of 0.05.
  
  
  RESULTS
  Two hundred twenty-seven distinct lymph nodes (22.5% positive for malignancy) were evaluated in 100 patients. Lymph node size, by CT scan and EBUS measurements, and round and oval shape were predictive of mediastinal metastasis. Increasing size of lymph nodes on EBUS was associated with increasing malignancy risk (P = .0002). When adjusted for CT scan size, hypermetabolic lymph nodes on PET scan did not predict malignancy. Echogenicity and border contour on EBUS and site of biopsy were not significantly associated with cancer. In 94.8% of lymph nodes with a clear diagnosis, the ROSE of the first pass correlated with subsequent passes.
  
  
  CONCLUSIONS
  Lymph node size on CT scan and EBUS and round or oval shape by EBUS are predictors of malignancy, but no single characteristic can exclude a visualized lymph node from biopsy. Further, increasing the number of samples taken is unlikely to significantly improve sensitivity.
authors.affiliation: Section of Pulmonary, Critical Care, and Respiratory Services, Washington Hospital Center, Washington, DC.
authors.forename: Jessica S
authors.initials: JS
authors.lastname: Wang Memoli
authors.affiliation: Palmetto Pulmonary and Critical Care Associates, Greenville, SC.
authors.forename: Ezzat
authors.initials: E
authors.lastname: El-Bayoumi
authors.affiliation: Division of Pulmonary, Critical Care, Allergy, and Sleep Medicine, Medical University of South Carolina, Charleston, SC.
authors.forename: Nicholas J
authors.initials: NJ
authors.lastname: Pastis
authors.affiliation: Division of Pulmonary, Critical Care, Allergy, and Sleep Medicine, Medical University of South Carolina, Charleston, SC.
authors.forename: Nichole T
authors.initials: NT
authors.lastname: Tanner
authors.affiliation: Pulmonary and Sleep Center of the Valley, Weslaco, TX.
authors.forename: Mario
authors.initials: M
authors.lastname: Gomez
authors.affiliation: Division of Pulmonary, Critical Care, Allergy, and Sleep Medicine, Medical University of South Carolina, Charleston, SC.
authors.forename: J Terrill
authors.initials: JT
authors.lastname: Huggins
authors.affiliation: Department of Medicine, Division of Biostatistics and Epidemiology, Medical University of South Carolina, Charleston, SC.
authors.forename: Georgiana
authors.initials: G
authors.lastname: Onicescu
authors.affiliation: Department of Medicine, Division of Biostatistics and Epidemiology, Medical University of South Carolina, Charleston, SC.
authors.forename: Elizabeth
authors.initials: E
authors.lastname: Garrett-Mayer
authors.affiliation: Department of Medicine, Division of Biostatistics and Epidemiology, Medical University of South Carolina, Charleston, SC.
authors.forename: Kent
authors.initials: K
authors.lastname: Armeson
authors.affiliation: Division of Pulmonary, Critical Care, Allergy, and Sleep Medicine, Medical University of South Carolina, Charleston, SC.
authors.forename: Katherine K
authors.initials: KK
authors.lastname: Taylor
authors.affiliation: Division of Pulmonary, Critical Care, Allergy, and Sleep Medicine, Medical University of South Carolina, Charleston, SC. Electronic address: silvestr@musc.edu.
authors.forename: Gerard A
authors.initials: GA
authors.lastname: Silvestri
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001707:Biopsy, Needle; D015331:Cohort Studies; D016001:Confidence Intervals; D019160:Endosonography / Q000379:methods; D005260:Female; D006801:Humans; D007150:Immunohistochemistry; D016015:Logistic Models; D008175:Lung Neoplasms / Q000000981:diagnostic imaging* / Q000473:pathology*; D008198:Lymph Nodes / Q000000981:diagnostic imaging / Q000473:pathology*; D008207:Lymphatic Metastasis; D008297:Male; D008875:Middle Aged; D009361:Neoplasm Invasiveness / Q000473:pathology; D009367:Neoplasm Staging / Q000379:methods*; D016017:Odds Ratio; D049268:Positron-Emission Tomography / Q000379:methods; D011237:Predictive Value of Tests; D011446:Prospective Studies; D014057:Tomography, X-Ray Computed / Q000379:methods