Endocrine Abstracts

Neuroendocrine tumours (NET) resulting in Cushing’s and Carcinoid syndrome(s) are rare. We present a case of a NET producing both ACTH and Serotonin with ensuing complexities in management. A 68 year old female, presented with a 5day history of weakness and increased stoma output requiring ITU admission for persistent hypokalaemia (K+2.2 mmol/l). Two months prior, she was diagnosed with a small bowel adenocarcinoma with liver metastases requiring palliative chemotherapy, on a background of extensive bowel surgery for Crohn’s disease. Investigations into her hypokalaemia revealed elevated levels of 9am cortisol (>1650nmol/l), ACTH (256.2ng/l), and 24hr urinary free cortisol (>3189nmol/l), consistent with ACTH dependant hypercortisolaemia. Apart from endogenous steroid induced hyperglycaemia, her clinical features of Cushing’s syndrome were minimal. A block and replace regime with adrenolytic Metyrapone and Hydrocortisone quickly normalised her cortisol and potassium levels. Review of her histopathology with neuroendocrine stains returned positive for synaptophysin, chromogranin A and CD-56, in keeping with a poorly differentiated NET, Ki 67 index 94%. Targeted chemotherapy with Oxaliplatin and Capecitabine was initiated. Further investigations showed elevated levels of Chromogranin A (280pmol/l) and Urine 5-HIAA (310umol/24hrs) in keeping with Carcinoid syndrome. Sandostatin LAR was started but she developed increased stoma output requiring gut rest and parenteral nutrition. Somatostatn analogue therapy was discontinued as it had no impact on her stoma output. A NM Octreotide SPECT CT scan confirmed evidence for somatostatin receptor positive liver metastases. The NET MDT outcome confirmed the rarity of octreotide avidity in a poorly differentiated NET and suggested the possibility of resuming somatostatin analogues. This and the role for any peptide related radiotherapy will be considered by the NET MDT at next review. This case highlights the need to investigate for multiple hormonal secretion from metastatic NET and the complexities in management when dual pathology is present.