OBJECTIVE Twelve patients to be undergone cholecystectomy and 4 patients to be undergone Billroth II gastric resection were examined before and after surgery in order to evaluate the association between duodenogastric reflux and gastric mucosal cell proliferation. Duodenogastric reflux was assessed by measuring the concentration of bile acids in gastric juice and expressed as fasting bile reflux in mumol/h. Gastric mucosal cell proliferation was assessed by measuring the concentration of polyamines (putrescine, spermidine and spermine) in biopsy specimens and expressed in mumol/g of tissue. RESULTS The median increase in fasting bile reflux was 34 mumol/h after cholecystectomy and 238 mumol/h after Billroth II gastric resection (P = 0.008). After cholecystectomy the median value of putrescine levels in antrum was 39 mumol/g, whereas after Billroth II gastric resection putrescine levels in pre-anastomotic area was 79.5 mumol/g (P = 0.008). There was a positive correlation between fasting bile reflux and putrescine levels either in antrum (r = 0.37, P = 0.04) or body (r = 0.48, P = 0.006). CONCLUSIONS The increase in cell proliferation activity of gastric mucosa after Billroth II gastric resection might explain the increased risk for cancer of gastric remnant.