Endocrine Abstracts

A 63-year-old Caucasian female was admitted with a 12-month history of exertional breathlessness, anxiety attacks, syncopal episodes, diarrhoea, fatigue, reduced appetite, two stones weight loss, and dry facial and truncal flushing. Investigations revealed raised Urine 5-HIAA of 116 (RR <50 μmol/24 h) and raised Chromogranin A of 48 (RR <6 nmol/l). CT scan revealed an extensive soft tissue mass encasing the upper abdominal aorta, compressing the inferior vena cava and extending down along the retroperitoneum and iliac vessels. The ureters were obstructed with consequent bilateral hydronephrosis. Renal function was normal. Renogram showed a non-functioning right kidney and functioning left kidney. NM octreotide SPECT CT showed increased focal activity in mediastinal, bilateral retroperitoneal and mesenteric adenopathy with no increased activity in the liver, lungs, bowel or skeleton. Para aortic lymph node histology was consistent with metastatic gastrointestinal well-differentiated neuro endocrine tumour with Ki67 index of 1%. She was referred to cardiology as NT-proBNP was elevated at 3239 ng/l. Despite only modest elevation in five HIAA, trans-oesophageal echocardiogram and cardiac MRI confirmed severe mitral regurgitation, moderate aortic and tricuspid regurgitation, and mild pulmonary regurgitation. In view of frailty and heart failure she was considered too unwell for replacement of all four valves. Hence she underwent aortic and mitral metallic valve replacement. She also underwent right ureteric stenting to relieve obstruction but this unfortunately led to septicaemia and infective endocarditis.

Carcinoid syndrome is usually associated with the presence of liver metastases. It can also occur in the absence of liver metastases if there is large retroperitoneal nodal involvement, draining directly into the systemic circulation and bypassing the portal circulation as in this patient. It is unusual for left side heart valves to be affected predominantly, as serotonin is normally inactivated in the lungs to 5-HIAA.