Successful EUS-guided ethanol ablation of insulinoma, four-year follow-up. Case report and literature review.

INTRODUCTION: EUS-guided ethanol ablation of insulinoma is a new method of treatment of this neuroendocrine tumour. Ablation is recommended in patients who are poor surgical candidates or refuse surgery. We present a case of an 81-year-old female with symptomatic insulinoma, treated successfully with EUS-guided alcoholic ablation, along with a literature review including 28 other previously described cases. The effectiveness, safety of the therapy, and technical procedure-related issues are summarised. To the best of our knowledge, this is the first described case of successful insulinoma EUS-guided ablation in Poland.

MATERIAL AND METHODS: We searched the PubMed/Medline database to identify cases of EUS-guided alcoholic ablation. Our analysis included 14 articles (case reports or case series), with a total of 27 patients and 31 tumours described, published before February 2017.

RESULTS: The described tumours were relatively small (mean 13 mm), and the most common location was pancreatic head. The mean ethanol volume injected to the tumour was 1.8 ml and the concentration of infused alcohol varied from 95% to 98%.Side effects were observed in six cases; apart from one, they were mild and self-limiting. There was only one severe adverse event, treated conservatively with success. The median follow-up was 14.4 months (2-55 months). In all described cases ablation led to improvement of the symptoms and normalisation of glycaemia.

CONCLUSIONS: The EUS-guided alcoholic ablation of insulinoma is a safe and effective method of treatment in patients who are poor surgical candidates and/or refuse surgery. The adverse effects are rare and mild and were observed when the volume of injected ethanol was equal to or above 3.0 ml. However, the data is limited, the follow-up is relatively short, and prospective studies are needed to confirm the long-term effects of treatment. The study shows also that there are important procedural differences (concentration and volume of alcohol, needle gauge, number of sessions) between the endoscopists, which should be specified.