[Carcinogenicity of duodenogastric reflux juice in patients undergoing gastrectomy].

OBJECTIVE

To determine the carcinogenic potential of reflux juice from patients undergoing remote gastrectomy and to clarify the relationship between duodenogastric reflux and gastric stump cancer.

METHODS

A total of 37 reflux juice samples (13 Billroth I, 24 Billroth II) were used. A two-stage transformation assay using BALB/c 3T3 cells was carried out to test the initiating or promoting activity of the samples.

RESULTS

11.1% reflux samples showed initiating activities, whereas 47.4% samples enhanced the MNNG-initiating cell transformation, suggesting that duodenogastric reflux juice might possess tumor-promoter activity (P < 0.05). There was no difference in initiating activities of the samples irrespective of surgical procedures (P > 0.05). Billroth II samples exhibited stronger tumor-promoter activity than Billroth I samples (P < 0.05), in accordance with many epidemic findings that this cancer preferred to Billroth II procedure. The promoter activities were well correlated with the histological changes of the stomas (r(s) = 0.625, P < 0.01), but both their cytotoxicities and initiating activities failed to show this correlation.

CONCLUSIONS

The duodenogastric reflux juice from patients undergoing remote gastrectomy has tumor-promoting activity on initiating activity. It is suggested that tumor-promoting potential should be responsible for the high incidence of gastric carcinoma in the patients undergoing remote gastrectomy. Thus a direct evidence for the etiology of gastric stump carcinoma is provided.