Endocrine Abstracts

We present a case report of a 56-year-old woman with MEN1 syndrome diagnosed at the age of 28 years. It was completely expressed by the set – insulinoma, prolactinoma and primary hyperparathyroidism. She underwent resection of 2/3 of the pancreas for symptomatic hypoglycaemia in the age of 28 years (1991). After two resections of parathyroid glands hypocalcaemia replacement was necessary. Prolactinoma was transiently treated with dopamine agonists. In the age of 45 years hypoglycaemia symptoms reappeared and a 30 mm recurrence of neuroendocrine tumour in the pancreatic head was detected. After its surgical enucleation (complicated with pancreatic fistula) hypoglycaemia symptoms improved, but did not completely disappeared. On abdominal ultrasound examination, small multiple hyperechogenic foci in the steatotic liver were observed. From the age of 53, the size of the largest lesion in segment VI progressed to 25 mm, then after one year to 30 mm. Clinical complaints included symptoms of hypoglycaemia – weakness, sweating, trembling hands, resolution of symptoms after eating. Whole-body scintigraphy after administration of ¹¹¹In-pentetreotide (Octreoscan) did not show expression of somatostatin receptors in the liver foci. A biopsy of the lesion in the right lobe of the liver followed in November 2022. The liver histology confirmed metastases of pancreatic insulinoma – NET G1 with the somatostatin receptors 5 (SSTRs-5) positivity (about 90% of cells, 2-3+). Recently, microwave ablation of the largest liver lesion was performed. The clinical manifestations were relieved and glycaemia normalized shortly after microwave liver ablation. In our case, recurrence of liver metastases of malignant insulinoma in the liver occurred 28 years after the diagnosis of MEN1 syndrome. The tumour strongly expressed SSTR-5 on liver metastases, but no SSTR-2 was revealed, which is rare and explains Octreoscan negativity. Thus, further pasireotide therapy was indicated with the aim of antisecretory and antiproliferative effect on neuroendocrine tumour.