In the current edition of the Thoracic Surgery News, published by the AATS, a note addresses the issue of mediastinoscopy vs. EBUS-TBNA. It’s a study presented at the last AATS meeting, done at the Toronto General Hospital in which EBUS-TBNA was found equally effective as mediastinoscopy when staging lung cancer. They enrolled 153 patients and performed EBUS-TBNA followed by mediastinoscopy in every patient and found EBUS-TBNA having 81% sensitivity, 91% negative predictive value and 93% diagnostic, and mediastinoscopy having 79% sensitivity, 90% negative predictive value, and 93% accuracy. Specificity and positive predictive was 100% for both methods.
EBUS-TBNA has become an essential part of the minimally invasive staging of the mediastinum. Mediastinoscopy has been done less frequently in patients with lung cancer for two reasons: the first one is the increased use of PET-CT; patients with small peripheral pulmonary nodules and negative mediastinum in PET-CT do not go routinely through mediastinoscopy. The second reason is that many other patients are diagnosed with mediastinal disease during EBUS-TBNA; these patients do not need mediastinoscopy because as shown by this study the EBUS-TBNA’s PPV is 100%. As a result, mediastinoscopy is left for those patients with suspicion of mediastinal disease in CT or PET-CT and a negative EBUS-TBNA. We have published about EBUS-TBNA vs. mediastinoscopy in the ATS.
I don’t think in terms of EBUS-TBNA replacing mediastinoscopy, but rather consider these two as complementary. EBUS-TBNA and mediastinoscopy complement each other in some situations as in the restaging of the mediastinum in patients with N2 disease that undergo neoadjuvant therapy. EBUS-TBNA can be use initially to stage the mediastinum and after neoadjuvant therapy mediastinoscopy used for restaging. Hiliar lymph node stations represent a spot which mediastinoscopy does not reach, but EBUS-TBNA can. Even though, it does not make a difference in treatment approach, in certain cases might be useful to know about these nodes.
Finally, Endoscopic Ultrasound with Fine Needle Aspiration (EUS-FNA) can add lymph node stations to the staging done by mediastinoscopy or EBUS-TBNA. Despite the infrequent involvement of stations #8 and #9 in lung cancer, EUS-FNA can sample these stations through the esophagus and also access the most posterior part of the subcarinal nodes.
I consider mediastinoscopy is still the gold standard in the invasive staging of the mediastinum, but we should get use to read reports favouring EBUS-TBNA and EUS-FNA to mediastinoscopy, based on better sensitivity and less complications. For us, as thoracic surgeons, the most important thing is to know how these techniques can complement each other, which ones are their limitations and flaws and based in this knowledge, tailor the best diagnostic strategy for every single patient.
Sebastian