Radiofrequency ablation of a solitary pancreatic insulinoma in a patient unsuitable for surgical resection
M Moriarty, C Lim, J Todd, Hammersmith Hospital.
We present the case of a 70 year-old, female referred from her local hospital with an eight month history of symptoms suggestive of hypoglycaemia. She reported weight gain associated with increased food intake and required regular snacks. A prolonged fast which confirmed hypoglycaemia at 20 hours (glucose 1.8mmol/L) with inappropriate insulin (17.3 milliunit/L) and c-peptide (2418 pmol/L) established the biochemical diagnosis of insulinoma. Gallium DOTATATE PET CT identified a single lesion measuring 16mm in the uncinate process of the pancreas.
Over the following months, her symptoms became more debilitating despite diazoxide therapy. She was admitted to hospital and required a dextrose infusion. She was not a suitable surgical candidate due her medical co-morbidities including severe COPD. A less invasive approach was considered and she proceeded to have radiofrequency ablation under endoscopic guidance. Following three sessions, she had resolution of her symptoms which was sustained at three months. A 72 hour fast demonstrated biochemical remission with no evidence of hypoglycaemia.
Imaging following treatment showed a cystic lesion with necrotic tissue in the centre which may be residual tissue or post inflammatory response. She will be monitored with further surveillance imaging.
Insulinomas are rare neuroendocrine tumours of the pancreas. Surgical resection or enucleation is considered the most effective treatment in localised disease for prolonged remission and cure. In patients who are unsuitable for surgery due to metastases or co existing medical conditions, pharmacological therapy with diazoxide or octreotide are alternatives. Radiofrequency ablation could be considered where expertise exists in patients who remain symptomatic on medical therapy. It may provide a less invasive alternative in those patients who are not suitable for surgical intervention.