Table 2.

Factors associated with diagnostic failure

Cases	Bronchi	EBUS-i	Diagnosis	Technical factors	Pathological factors
1	LtB1 + 2a	IIa	WDadeno	Bending and difficult stabilization of guide sheath	Tumor with central necrosis
2	RtB6c	IIb	MD adeno	Bending and difficult stabilization of guide sheath	Homogeneous distribution of tumor cells
3	RtB1bii	IIIa	MD adeno	No difficulty	Heterogeneous tissue. Tumor cells in granulomatous and fibrotic tissue
4	LtB3ci	IIIa	MD adeno	Bending of guide sheath	Tumor central necrosis
5	RtB10bii	IIIa	WD adeno	Bending and difficult stabilization of guide sheath	Tumor cells with predominant distribution in central areas
6	RtB4aiβ	IIIb	PD SCC	No difficulty	Tumor with central necrosis
7	RtB2bii	IIIa	WDadeno	No difficulty	Tumor with central necrosis
8	LtB8biiα	IIIb	DLBCL	Difficult stabilization of guide sheath	Homogeneous distribution of tumor cells

EBUS-1 endobronchial ultrasound image, LtB left bronchus, RtB right bronchus, adeno adenocarcinoma, SCC squamous cell carcinoma, WD well-differentiated, MD moderately differentiated, PD poorly differentiated, DLBCL diffuse large B cell lymphoma