When assessing a patient for lung cancer, a procedure involving the insertion of an EBUS scope in the esophagus – EUS-B-FNA – can achieve similarly accurate results as endoscopic ultrasound guided–fine-needle aspiration (EUS-FNA), according to a new study.

This finding could lead patients to choose EUS-B-FNA over EUS-FNA – the standard of care for analyzing potential metastasis of the left adrenal glands (LAGs) – resulting in both time and cost savings for patients.

The current standard of care involves using an EBUS scope for complete mediastinal and hilar staging of lung cancer or, if present, a tumor. This is then followed by an assessment of the LAG by conducting ultrasound guided–fine-needle aspiration with a different scope. However, in this study, the investigators included an experimental procedure between those two steps, which involved advancing the EBUS scope into the patients’ stomachs to find and assess the LAG. The idea is that, by using just one tool and technique rather than using an EBUS scope followed by the traditional EUS-FNA (which involves using a second scope), both the patient and the provider save time and money.

“A recent report showed that LAG visualization using the EBUS scope was possible in 85% of patients,” according to the authors of this study, including Prof. Jouke T. Annema, MD of the University of Amsterdam. Prior to this new research, it was unknown to what extent a single EBUS scope adequately assess and sample the LAGs and how its performance related to the use of a conventional endoscopic ultrasound–guided scope (Lung Cancer. 2017. doi: org/10.1016/j.lungcan.2017.02.011 ).

Dr. Annema and his coauthors recruited patients from four centers – three in the Netherlands, one in Poland – and followed them prospectively. Patients with “(suspected) lung cancer [who] had an indication for both mediastinal lymph node and LAG sampling” were recruited for the study. The researchers followed 44 patients through final diagnosis to determine if they ultimately had lung cancer.

Subjects first received complete mediastinal and hilar staging of lung cancer and any present tumors via an EBUS and EUS-B procedure. Following an EBUS examination of the mediastinum, the EBUS scope was retracted from the trachea and positioned into the esophagus for an examination of the mediastinal nodes. Then, the EBUS scope was advanced into the stomach for identification of the LAG. Afterward, the routine EUS-FNA was performed. LAG analysis across both methods involved visualizing the LAG and collecting an adequate tissue sample for testing.

“In short, in order to locate the LAG, a structured three step approach was used according to the EUS assessment tool (EUS-AT): identification of the liver, abdominal aorta, coeliac trunk, left kidney, and LAG,” the authors noted. “By turning the EBUS scope clockwise from the liver, the abdominal aorta and coeliac trun[k] are identified. By subsequently turning the EBUS scope gently in caudal direction, the left kidney and LAG are identified.”

Endoscopists then evaluated both procedures in each subject according to feasibility and practicability to determine if the findings of the experimental procedure were usable. Finally, a cytologic exam was conducted, using Giemsa or Papanicolaou staining to determine if any present cancer had metastasized, and a final diagnosis was made.

LAG analysis had a success rate of 89% (39/44; 95% confidence interval, 76-95%) for EUS-B-FNA, compared with 93% (41/44; 95% CI, 82-98%) for EUS-FNA. Similarly, when looking at the rate of sensitivity for LAG metastases, EUS-B had a rate of sensitivity for LAG metastases of at least 87% (95% CI, 65-97%), while EUS-FNA was found to be at least 83% (95% CI, 62-95%. Endoscopists were equally satisfied with both procedures in the “majority” of cases in this study.

“In [five] cases (11%), the EUS-B-FNA procedure was unsuccessful, due to the inability to make good contact of the ultrasound transducer and the stomach wall,” the authors explained. “The conventional EUS scope is more stable as a result of the increased tube diameter. Another advantage of the conventional echo-endoscope is its wider scanning angle. … The conventional EUS scope is also longer than the EBUS scope, [but that] does not seem to be the limiting factor.”

No funding source was disclosed for this study. The authors reported no relevant financial disclosures.