Abstract
Objective: The accuracy of rapid on-site evaluation (ROSE) during endobronchial ultrasonography with guide sheath (EBUS-GS) was reported to be approximately 90% for diagnosing small peripheral pulmonary lesions (PPLs). When ROSE during EBUS-GS for diagnosing small peripheral lung cancer is carried out and does not include malignant cells in a position whereby the probe was located within or adjacent to the lesion, the best technique for overcoming the lower diagnostic yield remains unknown. This study aimed to evaluate factors affecting positive results of ROSE during EBUS-GS in such a probe position. Moreover, when the results of ROSE were consistently negative, we evaluated the effectiveness of conventional transbronchial biopsy (TBB) in addition to EBUS-GS alone. Methods: We performed a retrospective analysis of consecutive patients who underwent EBUS-GS combined with ROSE for diagnosing small peripheral lung cancer (≤30 mm). We classified the results of ROSE into two groups based on the presence of malignant cells: the ROSE positive group (included malignant cells) and the ROSE negative group (did not include malignant cells). The significant predictors of positive ROSE results during EBUS-GS were analyzed using multivariate logistic regression analyses. Results: We identified 67 lesions (43 lesions in the ROSE positive group and 24 lesions in the ROSE negative group, respectively). Multivariate logistic analysis revealed that the significant factor affecting positive ROSE results was lesion size (>15 mm) (OR = 9.901). The diagnostic yield of additional conventional TBB to EBUS-GS was significantly higher than that of EBUS-GS alone (75.0% vs 33.3%, P = .041). Conclusion: The positive results of ROSE during EBUS-GS were significantly influenced by lesion size (>15 mm). When the results of ROSE during EBUS-GS were consistently negative in a position whereby the probe was located within or adjacent to the lesion, additional conventional TBB was effective to improve the diagnostic yield compared with EBUS-GS alone.