Role of endoscopic ultrasound for pre-intervention evaluation in early esophageal cancer

Table 5 Proportions of patients with deep invasion (T2 and beyond) having the endoscopic ultrasound parameters assessed compared to proportions of patients without deep invasion

Deep invasion on pathology		EUS parameter
		Presence of notable (but non-diagnostic) para-esophageal lymph nodes on EUS	Presence of positive lymph nodes by EUS criteria
Yes (T2 and beyond)	n1/N1 (%)	13/16 (81.2)	0/16 (0)
No (T1a and T1b)	n2/N2 (%)	11/33 (33.3)	0/33 (0)
P valuea		< 0.001	N/A

^aP value derived from chi-square test done to compare proportion of patients with deep invasion for each endoscopic or pathologic parameter (“Yes” row) to proportion of patients without deep invasion (“No” row).

n₁: Number of patients with factor being assessed AND deep invasion on pathology; n₂: Number of patients with factor being assessed AND no deep invasion on pathology; N₁: Number of patients with deep invasion on pathology and clinical data available regarding the presence or absence of each factor; N₂: Number of patients without deep invasion on pathology and clinical data available regarding the presence or absence of each factor. EUS: Endoscopic ultrasound; N/A: Not applicable.