David Swienton MBBCHIR, MA, Presenter: Nothing to Disclose

Amrita Bajaj MD, FRCR, Abstract Co-Author: Nothing to Disclose

Joseph Harry Mullineux BMBCh, BSC, Abstract Co-Author: Nothing to Disclose

Jonathan Bennett, Abstract Co-Author: Nothing to Disclose

Standard practice at our institution includes ultrasound of the neck in all patients with multistation N2 or N3 lung cancer. We examined whether supraclavicular lymphadenopathy on staging CT could be used to reliably predict whether lymph nodes suitable for sampling with fine needle aspiration (FNA) would be found on ultrasound of the neck.

Analysis of 361 ultrasound reports and the preceding CT scans was performed. The primary outcomes were whether CT scans with multistation N2 or N3 lung cancer demonstrated supraclavicular lymphadenopathy and if subsequent ultrasound demonstrated lymph nodes amenable to FNA. Subgroup analysis was used to determine predictors for the presence or absence of nodes suitable for tissue sampling.

Results were grouped accordingly: Supraclavicular lymph noded (LN) present on CT with: LN present on ultrasound (Group 1) or LN absent on ultrasound (Group 2); Supraclavicular LN absent on CT with: LN present on ultrasound (Group 3) or LN absent on ultrasound (Group 4). For both N2 and N3 stage lung cancer: Group 1, n = 84; Group 2, n = 12; Group 3, n = 17; Group 4, n = 179. Specificity 93.7%, Sensitivity 83.2%, NPV 91.3% and PPV 87.5%. Diagnostic odds ratio = 74 (95% CI 34 –161). For N3 disease: Group 1, n = 69; Group 2, n = 9; Group 3, n = 9; Group 4, n = 81. Specificity 90.0%, Sensitivity 88.5%, NPV 90.0% and PPV 88.5%. For N3 disease and those initially staged as N2 with supraclavicular LN on review of CT:Group 1, n = 84; Group 2, n = 12; Group 3, n = 9; Group 4, n = 81. Specificity 87.1%, Sensitivity 90.3%, NPV 90.0% and PPV 87.5%. For N2 disease including those with supraclavicular LN on review of CT (although these should have been classified as N3 originally):Group 1, n = 12; Group 2, n = 2; Group 3, n = 7; Group 4, n = 93. Specificity 97.9%, Sensitivity 63.2%, NPV 93.0% and PPV 85.7%

Overall CT of the chest is highly specific (94%) in ruling out whether lymph nodes suitable for tissue sampling will be found on neck ultrasound in the context of lung cancer with multistation N2 or N3 disease. Specificity of 98% can be achieved in N2 disease and sensitivity increased to 90% by selecting only N3 disease.

Selecting those patients most likely to have supraclavicular lymphadenopathy suitable for tissue sampling avoids exposing patients to unnecessary procedures and makes more efficient use of radiology services.

Swienton, D, Bajaj, A, Mullineux, J, Bennett, J, Getting it in the Neck: Predicting Whether Supraclavicular Lymph Nodes Suitable for FNA Will Be Found on Ultrasound in Patients with Lung Cancer.  Radiological Society of North America 2014 Scientific Assembly and Annual Meeting, - ,Chicago IL. http://archive.rsna.org/2014/14010457.html