Somatostatin Receptor Scintigraphy and Intraoperative Gamma Probe Detection in the Localisation and Treatment of Pancreatic Insulinoma

  • Dr Nelson Loh, Royal Perth Hospital, Australia
  • Dr William Macdonald, Royal Perth Hospital, Australia
  • Dr Marina Dunne, Royal Perth Hospital, Australia
  • Mr Sudhakar Rao, Royal Perth Hospital, Australia
  • Aims: We report a case of insulinoma that was successfully enucleated under radio-guidance after an initial unsuccessful laparotomy. This case highlights the utility of Somatostatin Receptor Scintigraphy (SRS) and gamma probe in the localisation and treatment of neuroendocrine tumours.

    Methods: The patient presented with recurrent hypoglycaemia. An abdominal CT scan identified a lesion in the uncinate process of the pancreas, however, laparotomy with use of intraoperative ultrasound failed to localise the lesion. SRS with SPECT/CT was then requested by the surgical team with a view to radio-guided surgery.

    Results: SRS demonstrated an octreotide-avid tumour in the posterior uncinate process of the pancreas, and confirmed suitability for radio-guided surgery. At re-exploration, the surgeon was again unable to palpate the lesion or localise it with intraoperative ultrasound, however, the lesion was successfully detected and removed with the use of a gamma probe. A post-operative SRS confirmed complete excision and histopathology was diagnostic of insulinoma.

    Conclusion: This case highlights the utility of SRS in the intraoperative localisation and surgical excision of neuroendocrine tumours. The lesion was unable to be localised clinically or with intraoperative ultrasound but was successfully detected with scintigraphic techniques. The surgical team acknowledge that the use of a gamma probe enabled enucleation of the insulinoma, which obviated the need for an invasive Whipple's procedure.