Circulating gastrin concentrations in patients at increased risk of developing colorectal carcinoma.

BACKGROUND AND AIM: An increase in circulating concentrations of gastrin or gastrin precursors such as progastrin and glycine-extended gastrin has been proposed to promote the development of colorectal carcinomas (CRC). The aim of this study was to investigate whether or not circulating gastrin concentrations were increased in patients with an increased risk of developing CRC. METHOD: Patients were divided according to their risk into the five following groups: familial adenomatous polyposis (n = 20), hereditary non-polyposis colorectal cancer (n = 53), cluster of common colorectal cancers (n = 13), personal history and/or family history of adenomatous polyps or CRC (n = 150) and controls (n = 42). Radioimmunoassay with four region-specific gastrin antisera was used to measure progastrin, glycine-extended gastrin (gastrin-gly), amidated gastrin (gastrin-amide), and total gastrin in peripheral blood taken at the time of colonoscopy. RESULTS: Compared with the control group, familial adenomatous polyposis patients had significantly higher median values of total gastrin (29.8 pM vs 16.9 pM, P = 0.003) and gastrin-amide (17.1 pM vs 12.0 pM, P = 0.015). Patients with a personal or family history of adenomatous polyps or CRC also had higher circulating concentrations of total gastrin (21.8 pM) compared with controls (P < 0.05), while patients from all groups who presented with an adenomatous polyp on the day of colonoscopy had higher concentrations of total gastrin, progastrin, and gastrin-amide than patients without polyps. CONCLUSION: Concentrations of gastrin precursors are increased in particular groups with an increased risk of developing CRC.