A combination of two endoscopic ultrasound techniques provides a highly accurate method of staging the mediastinum in patients with suspected lung cancer, according to a report in the February 6th issue of the Journal of the American Medical Association.
In the study, endobronchial ultrasound-guided fine-needle aspiration (EBUS-FNA) was found to be more sensitive than standard bronchoscopic needle aspiration in detecting mediastinal lymph node metastases: 69% vs. 36%. When EBUS-FNA was combined with transesophageal endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA), the sensitivity reached 93%.
The researchers believe that use of EBUS-FNA plus EUS-FNA could markedly reduce the number of patients requiring mediastinoscopy, an invasive, more risky staging method. If mediastinoscopy had only been performed in patients with a negative EBUS-FNA plus EUS-FNA result, then the procedure could have been avoided in 28% of patients.
"Other studies to date have primarily focused on a single procedure (EUS, or EBUS, or bronchoscopy)," lead author Dr. Michael B. Wallace, from the Mayo Clinic in Jacksonville, Florida, told Reuters Health. "Our study combined the two of these that we felt were most likely to have complementary and complete coverage of the mediastinal lymph node locations."
The new findings are based on a study of 138 patients with suspected lung cancer who underwent all three procedures for mediastinal staging. The results obtained with each was compared with final pathologic confirmation and with clinical results at 6- and 12-month follow-up.
In addition to the high sensitivity seen with EBUS-FNA plus EUS-FNA, a high negative predictive value was also achieved -- 97%. Further analysis showed that this combined approach was better than either procedure alone or traditional bronchoscopy at detecting mediastinal lymph nodes at any site and in evaluating patients without lymph node enlargement on chest CT.
In accordance with American College of Chest Physician guidelines, all patients with suspected lung cancer should have the mediastinum staged with a biopsy-based method, Dr. Wallace emphasized. "The choice of which method should be based on which is least invasive and available expertise. Our study demonstrates that with expertise in EUS-FNA and EBUS-FNA, this may be the least invasive and most accurate method of pre-operative staging of lung cancer."
