Échographie endobronchique et ganglions TEP positives dans le cancer broncho-pulmonaire

[Results of endobronchial ultrasound-guided transbronchial needle aspiration in lung cancer: importance of the lymph node involvement prevalence]

OBJECTIVE

We studied the non-surgical invasive staging by endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) and we detailed the differences of our series, in order to understand the criteria allowing to achieve a better performance.

METHODS

Retrospective observational study conducted between 2007 and 2011, including all patients with proven NSCLC who underwent EBUS-TBNA.

RESULTS

For the 92 EBUS-TBNA performed, we found a sensitivity of 78%, a specificity of 93%, a positive predictive value (PPV) of 98%, a negative predictive value (NPV) of 45%, an accuracy of 80% and a prevalence of lymph node involvement at 84%. A learning curve has been demonstrated and a significant difference was found based on the number of punctures by procedure (P=0.02) or on histological type (P=0.02). By analyzing the data of the literature, we have been able to demonstrate that the accuracy and the negative predictive value are correlated with the prevalence. If we take into account this correlation, we can consider the results of our study close to those of the literature.

CONCLUSION

We highlighted a number of criteria that will influence the diagnostic yield of EBUS-TBNA. While some have already been described, other criteria such as histological type or patient selection criteria are less discussed. The key point is the correlation between the prevalence and EBUS-TBNA results. Results of the assessment of lymph node involvement techniques should be interpreted according to the prevalence of lymph node involvement.

[Diagnostic flexible bronchoscopy. Recommendations of the Endoscopy Working Group of the French Society of Pulmonary Medicine]

These guidelines on flexible bronchoscopy depict important clues to be known and taken into account while practicing flexible bronchoscopy, in adult, except in emergency situations. This is a practical clarification. Safety conditions, complications, anesthesia, infectious risks, cleaning and disinfection are detailed from a review of the literature. Intensive care practice of bronchoscopy requires more attention due to higher risks patients and is discussed extensively. Standards and performances of the various sampling techniques complete this work. Indications for bronchoscopy, therapeutic and paediatric bronchoscopy are not covered in these guidelines.

Endobronchial ultrasound and value of PET for prediction of pathological results of mediastinal hot spots in lung cancer patients

SUMMARY

In the staging of lung cancer with positron emission tomography (PET) positive mediastinal lymph nodes, tissue sampling is required. The performance of transbronchial needle aspiration (TBNA) using linear endobronchial ultrasound (real-time EBUS-TBNA) under local anaesthesia and the value of PET for prediction of pathological results were assessed in that setting. The number of eluded surgical procedures was evaluated. All consecutive patients with suspected/proven lung cancers and FDG-PET positive mediastinal adenopathy were included. If no diagnosis was reached, further surgical sampling was required. Lymph node SUVmax (maximum standardized uptake value) was assessed in patients whose PET was performed in the leading centre. One hundred and six patients were included. The average number of TBNA samples per patient was 4.9+/-1.1. The prevalence of lymph node metastasis was 58%. Sensitivity, accuracy and negative predictive value of EBUS-TBNA in the staging of mediastinal hot spots were 95, 97 and 91%. Patients without malignant lymph node involvement showed lower SUVmax (respective median values of 3.7 and 10.0; p<0.0001). Surgical procedures were eluded in 56% of the patients. Real-time EBUS-TBNA should be preferred over mediastinoscopy as the first step procedure in the staging of PET mediastinal hot spots in lung cancer patients. In case of negative EBUS, surgical staging procedure should be undertaken. The addition of SUVmax cut-off may allow further refinement but needs validation.

Evolving role of interventional pulmonology in the interdisciplinary approach to the staging and management of lung cancer: bronchoscopic mediastinal staging of lung cancer

Mediastinal lymph node involvement is present in 26%-38% of patients with non-small-cell lung cancer at the time of diagnosis, and it is often the most significant factor in determining surgical resectability. Complete and accurate mediastinal staging of lung cancer is essential for determining prognosis and for guiding optimal treatment strategies. Computed tomography and positron emission tomography are the most widely used noninvasive means for mediastinal staging in lung cancer. However, based on their reported specificities, computed tomography and positron emission tomography findings should be verified by cytohistologic sampling. In recent decades, the technique of transbronchial needle aspiration (TBNA) has been developed, permitting the bronchoscopist to obtain cytohistologic material from the hilar and mediastinal lymph nodes adjacent to the tracheobronchial wall. The technique of TBNA has a great specificity, is safe and cost-effective compared with surgical methods, and can be performed during the initial diagnostic bronchoscopy. Transbronchial needle aspiration sensitivity is 76%-78% but is highly influenced by several factors. Endobronchial ultrasound has been proposed as a means for improving TBNA sensitivity. Recently, a new type of bronchoscope with a built-in convex ultrasound probe directly attached to the tip has been developed to guide TBNA under real-time imaging. Reports on this innovative technique reveal a sensitivity of 94%-95.7%, which is superior to the reported sensitivity of surgical methods. However, ultrasound-guided TBNA and traditional TBNA should be considered complementary techniques, because their integration is likely to become the optimal staging strategy for patients with lung cancer.