Download PDF
Open Access
CC BY 4.0 · Endoscopy 2026; 58(S 01): E87-E88
DOI: 10.1055/a-2767-1673
E-Videos

Effectiveness of immediate contrast-enhanced evaluation after endoscopic ultrasound-guided ethanol injection for a pancreatic neuroendocrine tumor

Authors

  • Shuntaro Mukai 

    1   Department of Gastroenterology and Hepatology, Tokyo Medical University, Tokyo, Japan

  • Atsushi Sofuni

    1   Department of Gastroenterology and Hepatology, Tokyo Medical University, Tokyo, Japan

  • Takayoshi Tsuchiya 

    1   Department of Gastroenterology and Hepatology, Tokyo Medical University, Tokyo, Japan

  • Ryosuke Tonozuka 

    1   Department of Gastroenterology and Hepatology, Tokyo Medical University, Tokyo, Japan

  • Kazumasa Nagai 

    1   Department of Gastroenterology and Hepatology, Tokyo Medical University, Tokyo, Japan

  • Noriyuki Hirakawa 

    1   Department of Gastroenterology and Hepatology, Tokyo Medical University, Tokyo, Japan

  • Takao Itoi

    1   Department of Gastroenterology and Hepatology, Tokyo Medical University, Tokyo, Japan
Further Information
Also available at
 
 PDF Download Permissions and Reprints

The efficacy of local ablation therapies such as endoscopic ultrasound-guided ethanol injection (EUS-EI) and radiofrequency ablation for small pancreatic neuroendocrine tumors (P-NETs, ≤15 mm, G1) has been reported [1] [2] [3] [4] [5]. However, the risk of recurrence due to residual tumor where treatment is inadequate remains a major issue. Here, we report a case showing the effectiveness of immediate contrast-enhanced EUS evaluation after EUS-EI for a small P-NET as a means of overcoming this issue.

A 63-year-old man had a 15-mm pancreatic tumor in the head of the pancreas. The tumor showed early enhancement on contrast-enhanced computed tomography (CE-CT) and contrast-enhanced EUS. A pathological diagnosis of the P-NET (G1) was made by EUS-guided tissue acquisition. The patient declined surgical treatment and requested minimally invasive local ablation therapy using EUS-EI. Three transgastric punctures were performed using a 25-gauge needle, and a total of 1.8 mL of ethanol was injected. Just after EUS-EI, a high-echo area spread within the tumor, revealing the injected region. However, after a short time, it appeared as a low-echo area, making it impossible to identify areas where injection was inadequate and residual tumor was present. When contrast-enhanced EUS was subsequently performed using 0.5 mL perfluorobutane (Sonazoid; Daiichi-Sankyo, Tokyo, Japan), the contrast effect in the tumor, which showed early enhancement before EUS-EI, almost completely disappeared immediately after EUS-EI, confirming that there were no areas where the injection was insufficient ([Fig. 1], [Video 1]). No residual tumor showing enhancement was observed in a CE-CT scan performed 3 days after EUS-EI, confirming complete ablation of the tumor ([Fig. 2]). Immediate CE-EUS evaluation after EUS-EI can be considered useful for residual tumor evaluation.

Zoom
Fig. 1 Contrast-enhanced endoscopic ultrasound (CE-EUS) findings before and after endoscopic ultrasound-guided ethanol injection (EUS-EI). (Top) The pancreatic tumor showed early enhancement on pre-treatment CE-EUS evaluation. (Bottom) Immediately after EUS-EI, early enhancement of the pancreatic tumor almost completely disappeared on CE-EUS evaluation.
The effectiveness of immediate contrast-enhanced endoscopic ultrasound (EUS) evaluation after EUS ethanol injection (EUS-EI) for a small pancreatic neuroendocrine tumor was shown.Video 1

Zoom
Fig. 2 Contrast-enhanced computed tomography (CE-CT) findings before and after EUS-guided ethanol injection (EUS-EI). At the location where the pancreatic tumor was enhanced on CE-CT before EUS-EI (left), no residual tumor was observed after EUS-EI (right), showing that complete ablation was achieved.

Endoscopy_UCTN_Code_TTT_1AS_2AI


Contributorsʼ Statement

Shuntaro Mukai: Conceptualization, Data curation, Writing – original draft. Atsushi Sofuni: Writing – review & editing. Takayoshi Tsuchiya: Project administration, Writing – review & editing. Ryosuke Tonozuka: Project administration, Writing – review & editing. Kazumasa Nagai: Project administration, Writing – review & editing. Noriyuki Hirakawa: Project administration, Writing – review & editing. Takao Itoi: Conceptualization, Project administration, Supervision, Writing – review & editing.

Conflict of Interest

The authors declare that they have no conflict of interest.


Correspondence

Shuntaro Mukai, MD
Department of Gastroenterology and Hepatology, Tokyo Medical University
6-7-1 Nishishinjuku, Shinjuku-ku
Tokyo 160-0023
Japan   

Publication History

Article published online:
20 January 2026

© 2026. The Author(s). This is an open access article published by Thieme under the terms of the Creative Commons Attribution License, permitting unrestricted use, distribution, and reproduction so long as the original work is properly cited. (https://creativecommons.org/licenses/by/4.0/).

Georg Thieme Verlag KG
Oswald-Hesse-Straße 50, 70469 Stuttgart, Germany


  Permissions and Reprints
Zoom
Fig. 1 Contrast-enhanced endoscopic ultrasound (CE-EUS) findings before and after endoscopic ultrasound-guided ethanol injection (EUS-EI). (Top) The pancreatic tumor showed early enhancement on pre-treatment CE-EUS evaluation. (Bottom) Immediately after EUS-EI, early enhancement of the pancreatic tumor almost completely disappeared on CE-EUS evaluation.
Zoom
Fig. 2 Contrast-enhanced computed tomography (CE-CT) findings before and after EUS-guided ethanol injection (EUS-EI). At the location where the pancreatic tumor was enhanced on CE-CT before EUS-EI (left), no residual tumor was observed after EUS-EI (right), showing that complete ablation was achieved.