N-nitroso composti e rischio di carcinoma del moncone gastrico

Analyses of biochemical and microbiological variables such as pH, N-nitroso compounds (NOC) concentration, nitrite concentration, total viable counts (TVC), nitrate-reductase positive bacterial counts (NRPBC), were carried out on 65 gastric juice samples. These samples were obtained during the endoscopic and bioptic study of 45 patients previously submitted to partial gastrectomy (23 Billroth I, 22 Billroth II) and 20 normal controls. In the 65 samples of gastric juice, NOC concentrations as well as nitrite concentrations, TVC and NRPBC, significantly increased with the pH rising. Significantly higher mean pH values, NOC concentrations and nitrite levels were found in partial gastrectomies than in normal controls. In relation to surgical methods, higher mean pH values (p < 0.001), NOC concentrations (p = 0.016), nitrite levels (p = 0.008), TVC (p = 0.004) and NRPBC (p = 0.016) were observed in the juices of patients with Billroth II as compared with Billroth I gastrectomies. Aside from the type of reconstruction, a significant relation was found between the degree of histological alterations of the stump mucosa and NOC concentration in the gastric juice. All these data demonstrate that the presence of NOC in the gastric juice of gastroresected patients can be considered a risk factor for carcinoma developing in the gastric stump and that Billroth II reconstruction involves a risk higher than those of Billroth I.