The present study aims to evaluate the feasibility, safety and efficacy of EUS-guided ethanol ablation of an insulinoma.

As the major insulinomas are functioning islet cell tumors, surgical resection is currently first-line therapy for or treatment of insulinomas. However, the surgical resection of pancreatic neoplasm is conditional for specific patients and may be associated with substantial life-threatening complications. Several studies declared that endoscopic ultrasound (EUS)-guided lavage may offer an alternative to surgical resection of insulinomas. Nevertheless, their sample sizes were small and conclusions were built based on short-term outcomes. In addition, the amount of ethanol administrated for different types of insulinomas were inconsistent among those studies.

The present study aims to evaluate the safety, feasibility and efficacy of EUS-guided ethanol ablation therapy of insulinomas. We will use cytopathology and immunohistochemistry in combination with EUS-FNA for diagnosis of insulinoma. After EUS-guided ethanol ablation therapy, the safety and efficacy will be assessed at the baseline and different time points during follow-up by physicians blinded to the treatment or control status.

Inclusion Criteria:

1. Adults: at least 18 years.
2. Patients with insulinomas which are evaluated by histopathology .
3. patients who have signed a written consent form.

Exclusion Criteria:

1. Patients whose condition is not suitable for the endoscopic procedure.
2. Patients who have blood coagulation dysfunction.
3. Patients who have mental disorders.
4. Patients who have mild or severe cardiorespiratory insufficiency.
5. Patients who have hypertension and could not be controlled to safe level.
6. Pregnant and lactating women.
7. Patients whose conditions are not suitable for the present study.