EUS-guided ethanol ablation of insulinomas: case series and literature review

Abstract

Surgical resection is a standard treatment for insulinomas; however, it is associated with a high risk of complications and limited to specific suitable candidates. In recent years, endoscopic ultrasound (EUS)-guided ethanol ablation of insulinomas has emerged as a new therapeutic option, especially for elderly patients and candidates unfit for surgery. We aimed to evaluate the feasibility and safety of this technique for insulinomas. Four patients diagnosed with insulinomas based on EUS-fine-needle aspiration and immunohistochemistry results underwent EUS-guided 95% ethanol ablation. A comprehensive literature review was performed to understand the current status of the feasibility, safety, and effects of EUS-guided ethanol ablation of insulinomas. EUS-guided ethanol ablation of insulinomas was successfully completed in all the 4 patients. There were no perioperative or postoperative complications. The patients were discharged at 3 days after the procedure. No recurrence of hypoglycemia or tumors was noted during follow-up (range, 3-6 months). Literature review showed 8 patients with insulinomas who underwent EUS-guided ethanol ablation. All the procedures were successful, with no need for further surgical treatment. Among these reviewed cases, 6 patients had no post-procedural complications, while other 2 patients showed a mild increase in the serum levels of lipase and/or pancreatic enzymes within 48 h post-procedure; furthermore, 1 of these 2 patients presented at a later date with medically controllable hematoma and ulceration. During follow-up, 6 patients remained asymptomatic and normoglycemic, while the 2 patients who presented post-procedural complications developed occasional mild confusion. EUS-guided ethanol ablation of insulinomas is an effective and safe modality, with an acceptable level of post-procedural complications. However, the long-term effects of this new therapeutic option need to be validated in a large randomized controlled trial with longer follow-up.

FIGURE 1

(A) CT showing no lesion in the pancreas. (B) EUS confirming the presence of a hypoecho and uniform lesions in the head of pancreas with 10 × 7.5 mm in size, adjacent to the porta vein and gastroduodenal artery. (C) EUS-FNA yielded cytology (Diff Quick, ×20) compatible with a neuroendocrine tumor, immunohistochemical result showed that heterocyst CK(+), CgA(+), Sgn(+). (D) A-22 gauge needle was inserted and a total of 0.5ml of 95% ethanol was injected in the lesion, the ethanol produced a hyperechoic infiltrate. CgA = chromogranin A, CK = creatine kinase, CT = computed tomography, EUS = endoscopic ultrasound, FNA = fine-needle aspiration.