[W.D.H.A. Syndrome due to occult neuroendocrine malignancy with concomitant liver metastases].

In June 1999, a 62-year-old man is hospitalised to evaluate the sonographic suspicion of liver metastases. The biopsy of the liver shows a malignant neuroendocrine tumour. Further diagnostic investigation including gastroscopy, colonoscopy, enteroclysis, thoracal and abdominal CT and somatostatin-receptor-scintigraphy does not localise the primary tumour. In the absence of clinical symptoms a wait and see procedure with clinical and imaging controls at regular intervals is arranged. Beginning in spring of 2001--nearly two years after the initial diagnosis--the patient suffers from progredient diarrhoea and weight loss leading to hospitalisation in September 2001. The existence of secretory diarrhoea, hypokalaemia and hypercalcaemia arouses suspicion of vipoma. This is proven by a remarkably elevated plasma concentration of vasoactive intestinal peptide (VIP). Once more, an accurate investigation is started but no primary tumour can be discovered despite extensive liver metastases. A vipoma is a rare differential diagnosis of secretory diarrhoea. This case report describes the remarkable constellation of liver metastases of a malignant neuroendocrine neoplasm without a primary tumour and the clinical presentation of a W.D.H.A. syndrome (watery diarrhoea, hypokalaemia and hypo- or achlorhydria). Despite extensive disease, therapy with octreotide and prednisolone provides a good clinical response.