Staging Non–Small Cell Lung Cancer

Abstract

During the staging process of non-small cell lung cancer (NSCLC), accurate mediastinal lymph node staging is a critical factor which affects patient outcome. Cervical mediastinoscopy has been considered the "Gold Standard" for mediastinal staging in NSCLC. Recently, there is an increasing interest in minimally invasive endoscopic mediastinal staging techniques. In particular, endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) uses ultrasound technology built into a flexible bronchoscope for real-time ultrasound-guided sampling of mediastinal lymph nodes. EBUS-TBNA has access to all of the mediastinal lymph nodes accessible by mediastinoscopy as well as N1 nodes. Based on the current evidence, EBUS-TBNA represents a minimally invasive procedure as an alternative to mediastinoscopy for mediastinal staging of NSCLC with discrete N2 or N3 lymph node enlargement, provided negative results are confirmed by surgical staging. Until we have the final results of the controlled comparative study of EBUS-TBNA versus mediastinoscopy, it is uncertain whether EBUS-TBNA will completely replace mediastinoscopy. It will also be important to incorporate new minimally invasive endoscopic techniques in the algorithm of lung cancer staging. EBUS-TBNA may be considered for initial staging of NSCLC in patients with suspicious mediastinal lymph nodes on noninvasive staging, provided negative results are confirmed by surgical staging. This will allow mediastinoscopy to be reserved for restaging after induction treatment. EBUS-TBNA also has potential for providing molecular diagnosis.

Bronchoscopic staging of lung cancer

“…Needles, 21-and 22-gauge, with an internal stylet for tip clearance are used for tissue aspiration during real-time EBUS-TBNA (Figure 2). The reach of CP-EBUS within the mediastinum is complimentary to the cervical mediastinoscope [Yasufuku and Keshavjee, 2010]. CP-EBUS can access the upper paratracheal (#2R, #2L), lower paratracheal (#4R, #4L), the subcarinal (#7), the hilar (#10), the interlobar (#11), and the lobar (#12) nodal stations.…”

Mediastinoscopy in the era of endobronchial ultrasound: when should it be performed?

“…More importantly, mediastinoscopy is an excellent test to discount the possibility of mediastinal involvement in lung cancer, with reported specificity of 100 % and negative predictive value of 91 % [5]. Mediastinoscopy will be negative for a patient who has involvement of the aortopulmonary lymph nodes (Stations 5, 6), the prevascular nodes (Station 3), the inferior pulmonary ligament nodes (Station 9), and the periesophageal nodes (Station 8), all of which are not accessible by the mediastinoscope [17].…”