Endobronchial Ultrasound-Guided Fine Needle Biopsy in the Diagnosis of Mediastinal Lymphadenopathy: A Randomized Trial.

BACKGROUND

The comparative sampling efficacy of endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) needles in mediastinal lymphadenopathy remains unclear. Would the fine needle biopsy (FNB), with its Franseen design, provide better results than the fine needle aspiration (FNA) during EBUS-TBNA?

METHODS

We performed a single-center, investigator-initiated, single-blinded, randomized, parallel-group, superiority trial between August 2022 and July 2023. Consecutive patients were randomly assigned (1:1) to undergo EBUS-TBNA with either 19-gauge (G) FNA or 22-G FNB. The primary endpoint was the diagnostic yield, while the secondary endpoints were specimen adequacy and complication rates.

RESULTS

The study included 150 patients with a mean age of 44.5±15.1 years (50.7% female patients). The diagnostic yield of FNB was not significantly different from FNA (94.7% vs. 89.3%; difference, 5.4%; 95% CI: -4.0% to 15.0%; P=0.23). Despite this, FNB had a higher rate of adequate tissue (98.6% vs. 86.7%; difference, 11.9%; 95% CI: 4.0%-22.0%; P<0.001) and larger core tissue (11.52 vs. 9.29 mm; mean difference, 2.23 mm; 95% CI: 1.4-3.1mm; P<0.001) than FNA. FNB showed a significantly higher diagnostic yield for histologic samples (90.7% vs. 76.0%; difference, 14.7%; 95% CI: 3.0-27.0; P=0.016) in post hoc analysis; however, this should be considered a hypothesis-generating finding. All procedures were well tolerated except for minor bleeding.

CONCLUSION

Despite similar diagnostic yields, FNB was more effective than FNA in providing larger, adequate core tissue samples. This improvement in specimen quality may suggest a potential clinical benefit for comprehensive diagnosis and advanced pathologic work-up.