The cckOMA syndrome and its relation to the Zollinger-Ellison syndrome: a diagnostic challenge.

OBJECTIVE: Among patients with enteropancreatic neuroendocrine tumor syndromes only one case with a cholecystokinin (CCK) secreting tumor has been reported. She had significant hyperCCKemia leading to a specific syndrome of severe diarrheas, weight loss, repeated duodenal ulcers and a permanently contracted gallbladder with gallstones. There are, however, reasons to believe that further CCKomas exist, for instance among Zollinger-Ellison patients with normal plasma gastrin concentrations. The present review is a call to gastroenterologists for awareness of such CCKoma patients. METHOD: After a short case report, the normal endocrine and oncological biology of CCK is described. Subsequently, the CCKoma symptoms are discussed with particular reference to the partly overlapping symptoms of the Zollinger-Ellison syndrome. In this context, the diagnostic use of truly specific CCK and gastrin assays are emphasized. The discussion also entails the problem of access to accurate CCK measurements. CONCLUSION: Obviously, the clinical awareness about the CCKoma syndrome is limited. Moreover, it is also likely that the knowledge about the necessary specificity demands of diagnostic gastrin and CCK assays have obscured proper diagnosis of the CCKoma syndromes in man.

The uncovering and characterization of a CCKoma syndrome in enteropancreatic neuroendocrine tumor patients.

OBJECTIVE: Neuroendocrine tumors in the pancreas and the gastrointestinal tract may secrete hormones which cause specific syndromes. Well-known examples are gastrinomas, glucagonomas, and insulinomas. Cholecystokinin-producing tumors (CCKomas) have been induced experimentally in rats, but a CCKoma syndrome in man has remained unknown until now. MATERIAL AND METHODS: Using a panel of immunoassays for CCK peptides and proCCK as well as for chromogranin A, we have examined plasma samples from 284 fasting patients with gastroenteropancreatic neuroendocrine tumors. In hyperCCKemic samples, plasma CCK was further characterized by chromatography. RESULTS: One of the patients displayed gross hyperCCKemia. She was a 58-year old woman with a pancreatic endocrine tumor, liver metastases, 500-1000-fold elevated basal CCK concentration in plasma, diarrhea, severe weight loss, recurrent peptic ulcer and bilestone attacks from a contracted gallbladder. The CCK concentrations in plasma were not affected by resection of the pancreatic tumor, but decreased to normal after hemihepatectomy with removal of the metastases. CONCLUSION: A CCKoma syndrome with severe hypersecretion of CCK exists in man. The duodenal ulcer disease and diarrhea with permanently low gastrin in plasma suggest that CCKomas may mimic gastrinoma-like symptoms, because CCK peptides are full agonists of the gastrin/CCK-B receptor.

A short history of neuroendocrine tumours and their peptide hormones.

The discovery of neuroendocrine tumours of the gastrointestinal tract and pancreas started in 1870, when Rudolf Heidenhain discovered the neuroendocrine cells, which can lead to the development of these tumours. Siegfried Oberndorfer was the first to introduce the term carcinoid in 1907. The pancreatic islet cells were first described in 1869 by Paul Langerhans. In 1924, Seale Harris was the first to describe endogenous hyperinsulinism/insulinoma. In 1942 William Becker and colleagues were the first to describe the glucagonoma syndrome. The first description of gastrinoma by Robert Zollinger and Edwin Ellison dates from 1955. The first description of the VIPoma syndrome by John Verner and Ashton Morrison dates from 1958. In 1977, the groups of Lars-Inge Larsson and Jens Rehfeld, and of Om Ganda reported the first cases of somatostatinoma. But only in 2013, Jens Rehfeld and colleagues described the CCK-oma syndrome. The most recently updated WHO classification for gastrointestinal neuroendocrine tumours dates from 2010.