Criteria for the glucagon provocative test in the diagnosis of gastrinoma.

Introduction: The glucagon provocative test is useful for the diagnosis of gastrinoma. The aim of this study was to determine the criteria for the glucagon provocative test.

Methods: This study reviewed 8 patients that underwent the glucagon provocative test preoperatively and in whom the diagnosis was confirmed as gastrinoma histologically. The glucagon provocative test was performed by administering glucagon (20 μg/kg) intravenously, followed by 20 μg/kg h for the next 30 min, and plasma gastrin levels were measured 3 and 1 min before and 3, 5, 7, 10, 15, 20, and 30 min after the administration of glucagon. This study evaluated the peak value of plasma gastrin and the time required to reach the peak.

Results: Two of the 8 patients had multiple endocrine neoplasm type 1. The basal plasma gastrin levels ranged from 524 to 10,300 pg/ml. The time required to reach the peak was 3-10 min for all patients. The increase in the peak from the basal value was 235-8,920 pg/ml, and the percentage of increase was 38-337 %.

Conclusions: These results suggest that a diagnosis of gastrinoma should thus be made when plasma gastrin levels peak within 10 min after glucagon administration, with an increase of greater than 200 pg/ml and greater than 35 % of the basal value.