International Association for the Study of Lung Cancer/American Thoracic Society/European Respiratory Society classification predicts occult lymph node metastasis in clinically mediastinal node-negative lung adenocarcinoma

Eur J Cardiothorac Surg. 2016 Jan;49(1):e9-e15. doi: 10.1093/ejcts/ezv316. Epub 2015 Sep 15.


Objectives: We investigated the role of the 2011 International Association for the Study of Lung Cancer, American Thoracic Society, and European Respiratory Society (IASLC/ATS/ERS) classification in predicting occult lymph node metastasis in clinically mediastinal node-negative lung adenocarcinoma.

Methods: We reviewed lung adenocarcinoma patients who had clinically N2-negative status, were evaluated by preoperative positron emission tomography combined with computed tomography (PET/CT) and had undergone lobectomy or pneumonectomy at Memorial Sloan Kettering Cancer Center (n = 297). Tumours were classified according to the 2011 IASLC/ATS/ERS classification. The associations between occult lymph node metastasis and clinicopathological variables were analysed using Fisher's exact test and logistic regression analysis.

Results: Thirty-two (11%) cN0-1 patients had occult mediastinal lymph node metastasis (pN2) whereas 25% of cN1 patients had pN2 disease. Increased micropapillary pattern was associated with increased risk of pN2 disease (P = 0.001). On univariate analysis, high maximum standard uptake value of the primary tumour on PET/CT (P = 0.019) and the presence of micropapillary (P = 0.014) and solid pattern (P = 0.014) were associated with occult pN2 disease. On multivariable analysis, micropapillary pattern was positively associated with risk of pN2 disease (odds ratio = 3.41; 95% confidence intervals = 1.42-8.19; P = 0.006).

Conclusions: The presence of micropapillary pattern is an independent predictor of occult mediastinal lymph node metastasis. Our observations have potential therapeutic implications for management of early-stage lung adenocarcinoma.

Keywords: Early stage; Lung cancer; Metastasis; Micropapillary; Non-small cell lung cancer.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

  • Academic Medical Centers
  • Adenocarcinoma / classification*
  • Adenocarcinoma / mortality*
  • Adenocarcinoma / pathology
  • Adenocarcinoma / surgery
  • Adenocarcinoma of Lung
  • Adult
  • Aged
  • Aged, 80 and over
  • Analysis of Variance
  • Cancer Care Facilities
  • Disease-Free Survival
  • Europe
  • Female
  • Follow-Up Studies
  • Humans
  • Internationality
  • Logistic Models
  • Lung Neoplasms / classification*
  • Lung Neoplasms / mortality*
  • Lung Neoplasms / pathology
  • Lung Neoplasms / surgery
  • Lymph Nodes / pathology*
  • Lymphatic Metastasis
  • Male
  • Middle Aged
  • Multivariate Analysis
  • Neoplasm Invasiveness / pathology
  • Neoplasm Staging
  • Pneumonectomy / methods
  • Pneumonectomy / mortality
  • Predictive Value of Tests
  • Retrospective Studies
  • Risk Assessment
  • Societies, Medical / standards
  • Survival Rate
  • Time Factors
  • Treatment Outcome
  • United States