REVERSIBILITY OF SECRETION OF GASTRIC-INHIBITORY POLYPEPTIDE IN LONG-TERM SURVIVORS AFTER PANCREATICODUODENECTOMY

To elucidate serial changes in GIP and insulin secretion late after ra dical pancreatoduodenectomy (PD) in patients with pancreatic head canc er, plasma levels of GIP and insulin were measured during oral glucose administration before, early after (mean 50.2 days) and late after (m ean 14.9 months) the operation. Basal plasma levels of GIP in the pati ents (n=6) were not different among these three studies. The levels di d not differ from those in normal controls (n=9). GIP secretion in res ponse to oral glucose before PD were significantly greater than normal controls. The GIP secretion early after PD were significantly less th an that before PD. Late after PD, the GIP secretion were significantly greater than that early after PD. An insulinogenic index was calculat ed in each patient as integrated incremental IRI over integrated incre mental glucose for 180 minutes. The indices in response to glucose ing estion before PD were significantly less than those of controls. The i ndices early after PD were significantly smaller than those before PD. Late after PD, the indices did not differ from those early after PD. In conclusion, in long-term survivors after radical pancreatoduodenect omy for pancreatic head cancer, GIP secretion in response to glucose i ngestion recovered but the pancreas may not respond adequately to the stimulation of GIP.