Diagnostic Performance of Endoscopic Ultrasonography with Water-Filled Balloon Method for Superficial Esophageal Squamous Cell Carcinoma.

BACKGROUND: Endoscopic ultrasonography (EUS) is a commonly used tool for preoperative depth diagnosis of superficial esophageal squamous cell carcinoma (ESCC). Probing EUS using the water-filled balloon method is a simple and safe examination. AIM: The aim of this study was to clarify the diagnostic performance of EUS with the water-filled balloon method for superficial ESCC compared to magnifying narrow-band imaging (ME-NBI). METHODS: We retrospectively examined 403 lesions in 393 consecutive patients diagnosed with ESCC and evaluated them with ME-NBI and EUS. Clinicopathological findings were collected, and the accuracy of the preoperative diagnosis was compared between ME-NBI and EUS-B. EUS examiners were not blinded to prior ME-NBI results, and EUS results may have been influenced by ME-NBI results. RESULTS: The pathological tumor depth of the EP/LPM in 152 lesions, MM/SM1 in 130 lesions, and deep submucosa (SM2/SM3) in 121 lesions was examined. The proportion of total lesions with an accurate diagnosis was significantly higher in EUS than in ME-NBI (67.7% versus 62.0%, P = 0.015). When analyzed by clinical depth diagnosis using ME-NBI, the proportion of lesions with an accurate diagnosis was significantly higher for EUS in MM/SM1 (55.7% versus 46.1%, P = 0.033). The sensitivity was significantly higher in EUS for SM2/SM3 lesions (76.0% versus 54.5%, P < 0.001). The accuracy and specificity of EUS, which differentiate MM/SM1 from EP/LPM or SM2/SM3, were significantly higher than those of ME-NBI. The median endoscopic ultrasonography procedure time was approximately 6.5 min. CONCLUSIONS: EUS with the water-filled balloon method is a safe and straightforward method that can be performed on lesions clinically diagnosed as MM/SM1 using ME-NBI. We retrospectively reviewed lesions in patients diagnosed with ESCC and evaluated them using magnifying endoscopy with narrow-band imaging (ME-NBI) and endoscopic ultrasound using the water-filled balloon method (EUS-B). We conclude that EUS-B can increase the diagnostic accuracy.