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Background: Cushing’s syndrome (CS) in a patient with VHL has been attributed to a number of possible causes; pancreatic NET and renal cell carcinoma. The precise location of ectopic ACTH aid enormously in the management of VHL. Clinical case: A 31-year-old woman with Type 2 diabetes and family history of VHL presented with florid features of CS in her second trimester of pregnancy. A diagnosis of ACTH dependent CS was made based on elevated 24h urinary cortisol (1122 and 2448nmol/24hr, n<150-800), midnight cortisol (1322nmol/L, n<220nmol/L) and a detectable ACTH level (18.8pg/mL, n<10pg/mL). She underwent emergency caesarean section due to pre-eclampsia at 28 week gestation. Post-delivery, her morning cortisol was 2823nmol/L (n:171-536nmol/L). MRI pituitary was reported as normal. CT abdomen showed an enlarged pancreas which was almost completely cystic and a right renal mass (3.7 X 2.6 X 4cm). Serum chromogranin A was elevated (530.2ng/mL, n:27-94). 24h urinary free metanephrine was normal. Selective ACTH sampling was done together with bilateral inferior petrosal sinus sampling to elicit source of ACTH. Increased gradient of ACTH level compared to the periphery (138.9pg/mL vs. samples from IVC:115.1 pg/mL, renal vein:100.2 pg/mL) was detected from the hepatic vein that drains the pancreas via the portal venous system. Ketoconazole and metyrapone were given to control the cortisol level close to 600nmol/L prior to surgery. Preoperatively, IV hydrocortisone 100mg was administered, with additional 50mg given every 4 hours intraoperatively. Total pancreatectomy and right nephrectomy were performed. Inotropic support was required five hours into the surgery. Hydrocortisone was tapered down to a maintenance dose of 10mg, 5mg and 2.5mg TDS over 7 days. A week after surgery, am cortisol was 103nmol/L suggesting successful removal of ectopic ACTH source. Histopathological examination identified a solid tumour (18X12X12 mm) at the pancreatic tail which stained positive to Chromogranin A, synaptophysin and weakly positive to CD56. The mitoses was 0-1/10hpf with a Ki67 index of 2%. ACTH staining was positive. The renal mass was a Grade 1 clear cell renal cell carcinoma with equivocal ACTH staining. Two months later, there was resolution of cushingoid features. DOTATE and FDG/PET scans along with close surveillance using serum Chromogranin A and 6 monthly abdominal imaging were planned. Conclusion: When managing VHL with CS, there is always a possibility of more than one source of ACTH production. In delineating the cause of CS the use of selective ACTH sampling may be considered where functional imaging (DOTATATE) is unavailable. Reference : (1) Tamura K, Nishimori I, Ito T, Yamasaki I, Igarashi H, Shuin T. Diagnosis and management of pancreatic neuroendocrine tumor in von hippel-lindau disease. World J Gastroenterol . 2010;16(36):4515-4518. doi:10.3748/wjg.v16.i36.4515

Background: Insulinoma is the most common type of functioning pancreatic neuroendocrine tumor (NET). Polyhormonal secretions from the NET, giving rise to distinct clinical symptoms such as carcinoid symptoms are rare. Clinical Case: We report a 68-year-old woman who presented with four months history of recurrent diaphoresis, palpitations, tremors and chest tightness. These were associated with episodic paroxysms of flushing and diarrhoea. The physical examination was unremarkable. She was a well-nourished woman with BMI of 28 kg/m2. Initial laboratory tests ruled out any renal, liver abnormalities with normal cortisol and thyroid function test. Further evaluation confirms insulin mediated hypoglycaemia with low random blood sugar 2.5 mmol/l (4.4-7.8) and failure to suppress C-peptide, 1092 pmol/L (298-2350) and insulin levels, 12.7 mU/L (3-25). Urine 5-HIAA was markedly elevated 2430.37 µmol/day (3.66-42.89) with borderline elevation of serum chromogranin A level 122 ng/mL (27-94). IGF-1 was also raised at 416 ug/L (91-282). Two months later she presented with new onset of delirium, incoherence, agitation and restlessness independent of her hypoglycaemic events. These symptoms deteriorated and fluctuates throughout the day with period of normalcy in between. This has led to requirement of a full time caregiver for her. Cranial CT excluded any brain pathology. We are faced with a diagnostic challenge to localize the primary lesion as radiological imaging so far were normal. GALLIUM-68 PET CT showed physiological uptake in the uncinate process of the pancreas (SUVmax 14.4). Endoscopic ultrasound of the pancreas was normal. An intra-arterial calcium stimulation test with hepatic venous sampling (ASVS) confirms a lesion at the head of pancreas with two times increment of insulin from baseline at the gastroduodenal artery distribution. Despite elimination of hypoglycaemic events with Diazoxide 100mg twice daily, her neuropsychiatric symptoms persisted. We postulate that this might be from excessive peripheral production of serotonin by the pancreatic carcinoid tumour or a niacin deficiency state because of metabolic diversion of its precursor, tryptophan. Conclusion: This case highlights the occurrence of debilitating neuropsychiatry manifestations in a likely neuroendocrine tumour arising from the head of pancreas secreting insulin, serotonin and IGF-1.